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【327723】2022年江苏省镇江市中考数学真题

时间:2025-01-20 20:05:15 作者: 字数:23930字
简介:

绝密·启用前

2022年江苏省镇江市中考数学真题

题号

总分

得分





注意事项:

1.答题前填写好自己的姓名、班级、考号等信息

2.请将答案正确填写在答题卡上



评卷人

得分




一、填空题

1.计算:3+(﹣2)=_____

2.使 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 有意义的x的取值范围是( )

3.分解因式: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> _________

4.一副三角板如图放置, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> _________ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

5.已知关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 有两个相等的实数根,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> _________

6.某班40名学生体重的频数分布直方图(不完整)如图所示,组距为_________ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

7.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的中点,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> _________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

8.《九章算术》中记载,战国时期的铜衡杆,其形式既不同于天平衡杆,也异于称杆衡杆正中有拱肩提纽和穿线孔,一面刻有贯通上、下的十等分线.用该衡杆称物,可以把被称物与砝码放在提纽两边不同位置的刻线上,这样,用同一个砝码就可以称出大于它一倍或几倍重量的物体.图为铜衡杆的使用示意图,此时被称物重量是砝码重量的_________倍.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

9.反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像经过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 两点,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,写出符合条件的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的值_________(答案不唯一,写出一个即可).

10.五月天山雪,无花只有寒”,反映出地形对气温的影响.大致海拔每升高100米,气温约下降 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> .有一座海拔为2350米的山,在这座山上海拔为350米的地方测得气温是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,则此时山顶的气温约为_________ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

11.如图,有一张平行四边形纸片 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,将这张纸片折叠,使得点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 落在边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 上,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的对应点为点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,折痕为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,若点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 在边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 上,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 长的最小值等于_________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

12.20212022202320242025这五个数中任意抽取3个数.抽到中位数是20223个数的概率等于_________

评卷人

得分




二、选择题

13.下列运算中,结果正确的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

14.如图,数轴上的点A和点B分别在原点的左侧和右侧,点AB对应的实数分别是ab,下列结论一定成立的是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

15.珍爱地球,人与自然和谐共生”是今年世界地球日的主题,旨在倡导公众保护自然资源.全市现有自然湿地28700公顷,人工湿地13100公顷,这两类湿地共有(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 公顷
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 公顷
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 公顷
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 公顷

16.如图,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 在网格中小正方形的顶点处, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 相交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,小正方形的边长为1,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的长等于(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
A
2
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

17.1组数据为:000111,第2组数据为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,其中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是正整数.下列结论:①当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,两组数据的平均数相等;②当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,第1组数据的平均数小于第2组数据的平均数;③当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,第1组数据的中位数小于第2组数据的中位数;④当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,第2组数据的方差小于第1组数据的方差.其中正确的是(       
A
.①②
B
.①③
C
.①④
D
.③④

18.如图,在等腰 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> BC=  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 同时与边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的延长线、射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 相切, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的半径为3.将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 绕点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 按顺时针方向旋转 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的对应点分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,在旋转的过程中边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 所在直线与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 相切的次数为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
A
1
B
2
C
3
D
4

评卷人

得分




三、解答题

19.1)计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2)化简: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

20.1)解方程: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2)解不等式组: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

21.一只不透明的袋子中装有2个白球、1个红球,这些球除颜色外都相同.
(1)
搅匀后从中任意摸出一个球,摸到红球的概率等于_________
(2)
搅匀后从中任意摸出一个球,记录颜色后放回、搅匀,再从中任意摸出一个球.用列表或画树状图的方法,求2次都摸到红球的概率.

22.某地交警在一个路口对某个时段来往的车辆的车速进行监测,统计数据如下表:

车速( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

40

41

42

43

44

45

频数

6

8

15

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

3

2


其中车速为4043(单位: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> )的车辆数分别占监测的车辆总数的12%32%
(1)
求出表格中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的值;
(2)
如果一辆汽车行驶的车速不超过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 10%,就认定这辆车是安全行驶.若一年内在该时段通过此路口的车辆有20000辆,试估计其中安全行驶的车辆数.

23.某公司专业生产某种产品,6月初(当月月历如图)接到一份求购5000件该产品的订单,要求本月底完成,71日按期交货.




1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30




经盘点目前公司已有该产品库存2855件,补充原材料后,从本月7日开始生产剩余数量的该产品,已知该公司除周六、周日正常休息外,每天的生产量相同.但因受高温天气影响,从本月10日开始,每天的生产量比原来减少了25件,截止到17日生产结束,库存总量达3830件.如果按照10日开始的生产速度继续生产该产品,能否按期完成订单?请说明理由.如果不能,请你给该公司生产部门提出一个合理的建议,以确保能按期交货.

24.如图,一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
(1)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> _________ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> _________
(2)
连接并延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴上,若以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 为顶点的三角形与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 相似,求点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的坐标.

25.如图1是一张圆凳的造型,已知这张圆凳的上、下底面圆的直径都是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,高为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> .它被平行于上、下底面的平面所截得的横截面都是圆.小明画出了它的主视图,是由上、下底面圆的直径 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 以及 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 组成的轴对称图形,直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 为对称轴,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 分别是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的中点,如图2,他又画出了 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 所在的扇形并度量出扇形的圆心角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,发现并证明了点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 上.请你继续完成 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 长的计算.
参考数据: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

26.已知,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 分别在正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 上.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
(1)
如图1,当四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是正方形时,求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
(2)
如图2,已知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的大小有_________关系时,四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是矩形;
(3)
如图3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 相交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,已知正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的边长为16 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 长为20,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的面积取最大值时,判断四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是怎样的四边形?证明你的结论.

27.一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像经过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 、原点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 和一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 图像上的点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
(1)
求这个二次函数的表达式;
(2)
如图1,一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 与二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ),过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 作直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 作直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> _________ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> _________(分别用含 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的代数式表示);
证明: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
(3)
如图2,二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像是由二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像平移后得到的,且与一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> (点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 在点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的左侧),过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 作直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 作直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴,设平移后点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的对应点分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 相等吗?请说明你的理由;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的值.

28.操作探究题
(1)
已知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是半圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的直径, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是正整数,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 不是3的倍数)是半圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的一个圆心角.
操作:如图1,分别将半圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的圆心角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 14510)所对的弧三等分(要求:仅用圆规作图,不写作法,保留作图痕迹);
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
交流:当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,可以仅用圆规将半圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的圆心角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 所对的弧三等分吗?
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
探究:你认为当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 满足什么条件时,就可以仅用圆规将半圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的圆心角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 所对的弧三等分?说说你的理由.
(2)
如图2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的圆周角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> .为了将这个圆的圆周14等分,请作出它的一条14等分弧 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> (要求:仅用圆规作图,不写作法,保留作图痕迹).
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

参考答案

1.1

【解析】
根据有理数的加法法则计算即可.
3+(﹣2)
+(3﹣2)
1
故答案为1

2.x≥3

【解析】
根据二次根式有意义的条件,可推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,然后通过解不等式,即可推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
解:若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,原根式有意义,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故答案为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

3. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ## <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

【解析】
提公因式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,即可求解.
解:原式= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

4.105

【解析】
根据平行性的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,根据三角形的外角的性质即可求解.
解:如图,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故答案为:105
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

5.4

【解析】
一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的根与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 有如下关系:当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,方程有两个不相等的实数根;当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,方程有两个相等的实数根;当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,方程无实数根.利用判别式的意义得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,然后解关于m的方程即可.
解:根据题意得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
解得m=4
故答案为:4

6.5

【解析】
根据频数分布直方图中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 即可求解.
解:依题意,组距为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> kg,
故答案为:5

7.1

【解析】
由直角三角形斜边中线的性质得出AB=2DE,再由三角形中位线的性质可得FG的长;
解:∵RtABC中,点EAB的中点,DE=1
AB=2DE=2
FG分别是ACBC中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故答案为:1

8.1.2

【解析】
设被称物的重量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,砝码的重量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,根据图中可图列出方程即可求解.
解:设被称物的重量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,砝码的重量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,依题意得,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故答案为:1.2

9.1(答案不唯一,取 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的一切实数均可)

【解析】
先根据已知条件判断出函数图象所在的象限,再根据系数k与函数图象的关系解答即可.
解:∵反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像经过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 两点,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
此反比例函数的图象在二、四象限,
k0
k可为小于0的任意实数.
例如,k=﹣1等.
故答案为:﹣1(答案不唯一,取 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的一切实数均可)

10.6或零下6

【解析】
根据题意“海拔每升高100米,气温约下降 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ”,列出式子即可求解.
解:山顶的气温约为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故答案为:-6或零下6

11.2

【解析】
根据题意, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 点与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 点重合时,符合题意,据此即可求解.
解:∵将这张纸片折叠,使得点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 落在边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 上,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的对应点为点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 点与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 点重合时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,此时 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的长最小,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故答案为:2

12. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

【解析】
根据题意画出树状图,结合概率公式即可求解.
解:根据题意,画树状图如图,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2022
为中位数的情形有6种,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2022
为中位数的情形有6种,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2022
为中位数的情形有2种,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2022
为中位数的情形有2种,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2022
为中位数的情形有2种,
共有60种情况,其中抽到中位数是20223个数的情况有18种,
则抽到中位数是20223个数的概率等于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

13.C

【解析】
根据合并同类项法则,同底数幂的乘法法则,幂的乘方法则逐项计算即可判断选择.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,故A计算错误,不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,故B计算错误,不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,故C计算正确,符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,故D计算错误,不符合题意.
故选C

14.D

【解析】
依据点在数轴上的位置,不等式的性质,绝对值的意义,有理数大小的比较法则对每个选项进行逐一判断即可得出结论.
解:由题意得:a0b,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,∴A选项的结论不成立;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,∴B选项的结论不成立;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,∴C选项的结论不成立;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,∴D选项的结论成立.
故选:D

15.B

【解析】
科学记数法的表示形式为a× <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的形式,其中1≤|a|10n为整数.确定n的值时,要看把原数变成a时,小数点移动了多少位,n的绝对值与小数点移动的位数相同.当原数绝对值≥10时,n是正整数;当原数的绝对值<1时,n是负整数.
解:287001310041800 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> (公顷),
故选:B

16.A

【解析】
先根据勾股定理计算AD的长,再根据AOB∽△DOC,对应边成比例,从而求出AO的长.
解: AD= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> AB=2CD=3
ABDC
AOB∽△DOC
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
AO=2x,则OD=3x
AO+OD=AD
∴2
x+3x=5
解得:x=1
AO=2
故选:A

17.B

【解析】
根据平均数、中位数、方差的求法分别求解后即可进行判断.
解:①第1组数据的平均数为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
mn时,第2组数据的平均数为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故①正确;
1组数据的平均数为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,mn2n,则第2组数据的平均数为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
1组数据的平均数大于第2组数据的平均数;
故②错误;
1组数据的中位数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,若mn是奇数,则第2组数据的中位数是1;当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,若mn是奇数,则第2组数据的中位数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
即当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,第2组数据的中位数是1
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,第1组数据的中位数小于第2组数据的中位数;
故③正确;
1组数据的方差为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,第2组数据的方差为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,第2组数据的方差等于第1组数据的方差.
故④错误,
综上所述,其中正确的是①③;
故选:B

18.C

【解析】
首先以A为圆心,以BC边的中线为半径画圆,可得⊙A的半径为3,计算出OA的长度,可知⊙O与⊙A相切,根据两个相切圆的性质,即可得到答案.
解:如图:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
ADBC,以A为圆心,以AD为半径画圆
ACAB所在的直线与⊙O相切,令切点分别为PQ,连接OPOQ
AO平分∠PAQ
∵∠CAB=120°
∴∠
PAO=30°
OP=3
AO=  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> =6
∵∠
BAC=120°AB=AC   
∴∠ACB=30°CD=  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> BC=  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
AD=  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> =3
∴⊙
A的半径为3,
∴⊙
O与⊙A的半径和为6
AO=6
∴⊙
O与⊙A相切
ADBC
BC所在的直线是⊙A的切线
BC所在的直线与⊙O相切
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> =360°时,BC所在的直线与⊙O相切
同理可证明当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> =180°时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 所在的直线与⊙O相切.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> AO时,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> =90°时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 所在的直线与⊙O相切.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 90°180°360°时,BC所在的直线与⊙O相切
故答案选C

19.1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ;(2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

【解析】
1)直接利用特殊角的三角函数值、负整数指数幂的性质、绝对值的性质分别化简,再利用实数加减运算法则计算得出答案.
2)先对括号内的分式通分,然后再将除法转化为乘法,然后约分即可..
1)解:原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2)解:原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

20.1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ;(2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

【解析】
1)分式方程去分母转化为整式方程,求出整式方程的解得到x的值,经检验即可得到分式方程的解;
2)分别求出不等式组中两不等式的解集,找出两解集的公共部分即可.
1)解:方程两边同时乘以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> .得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
检验:当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
所以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是原方程的解;
2)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
解不等式①,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
解不等式②,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
所以原不等式组的解集是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

21.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

【解析】
1)根据概率公式直接求解即可;
2)画树状图求概率即可求解.
1
解:共有3个球,其中红球1个,
摸到红球的概率等于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2
画树状图如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
9种结果,其中2次都摸到红球的结果有1种,
∴2
次都摸到红球的概率 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

22.(1)16
(2)19200


【解析】
1)由车速的占比求得总的车辆数,然后相乘可得
2)先计算安全行驶的占比,再用该占比估算即可
1
方法一:由题意得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
方法二:由题意得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2
由题意知,安全行驶速度小于等于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
因为该时段监测车辆样本中安全行驶的车辆占总监测车辆的占比为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
所以估计其中安全行驶的车辆数约为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> (辆)

23.不能,理由见解析,为确保按期交货,从20日开始每天的生产量至少达到130

【解析】
10日开始每天生产量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 件,根据题意列出一元一次方程,继而根据,如果按照公司10日开始的生产速度继续生产该产品,截止月底生产的天数为9天,列出一元一次不等式,求得从20日开始每天的生产量至少达到130件,即可求解.
解:设10日开始每天生产量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 件,
根据题意,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
解得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
如果按照公司10日开始的生产速度继续生产该产品,截止月底生产的天数为9天,
因此该公司9天共可生产900件产品.
因为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,所以不能按期完成订单,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
所以为确保按期交货,从20日开始每天的生产量至少达到130件.

24.(1)42
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

【解析】
对于(1),将点A的坐标代入两个关系式,即可得出答案;
对于(2),先求出AOBOCO,再确定点D的位置,然后分两种情况 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,再根据相似三角形的对应边成比例求出答案即可.
1
将点A14)代入一次函数y=2x+b,得
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
一次函数的关系式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
将点A14)代入反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,得
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
反比例函数的关系式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故答案为:42
2
A与点C关于原点对称,可知点C的坐标是(-1-4).
x=0时,y=2
B02),
∴OB=2

根据勾股定理可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
当点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 落在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴的正半轴上,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 不可能相似.
当点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 落在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴的负半轴上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> .
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
综上所述:点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

25.42cm

【解析】
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> .设直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,根据圆周角定理可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,进而求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的长,即可求解.
解:连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> .设直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的中点,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 中,∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是对称轴,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
该图形为轴对称图形,张圆凳的上、下底面圆的直径都是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

26.(1)见解析
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
(3)
平行四边形,证明见解析

【解析】
1)利用平行四边形的性质证得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,根据角角边证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2)当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,证得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是等腰直角三角形,∠HEF=∠EFG=90°,即可证得四边形EFGH是矩形.
3)利用正方形的性质证得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 为平行四边形,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,垂足为点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,由平行线分线段成比例,设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,则可表示出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,从而把△OEH的面积用x的代数式表示出来,根据二次函数求出最大值,则可得OE=OGOF=OH,即可证得平行四边形.
1
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 为正方形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 为正方形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ;证明如下:
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 为正方形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> AB=BC=AD=CD
AE=AHCF=CGAE=CF
AH=CG
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
EH=FG
AE=CF
ABAE=BCCF,即BE=BF
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是等腰直角三角形,
∴∠
BEF=∠BFE=45°
AE=AHCF=CG
∴∠
AEH=∠CFG=45°
∴∠
HEF=∠EFG=90°
EHFG
四边形EFGH是矩形.
3
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 为正方形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 为平行四边形.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,垂足为点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的面积最大,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 是平行四边形.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

27.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
(2)①
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ;②见解析
(3)①
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,理由见解析;②3

【解析】
1)通过一次函数表达式可以求出AB两点坐标,将ABC三点坐标代入二次函数表达式即可求解;
2)①通过联立关系式可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,利用公式法解一元二次方程,求出方程的解即可得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的值;
通过A-20),E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 即可求出AE的长度;
通过B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> F <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 即可求出BF的长度;
3)①通过二次函数平移前后的表达式可以确定新二次函数的图像是由原二次函数的图像向右平移 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 个单位,向上平移3个单位得到的,从而可以得到: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> .通过联立关系式可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,利用公式法解一元二次方程,求出方程的解即可得到点PQ的横坐标,通过坐标即可表示出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的长度.
由①可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,求解即可.
1
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
将点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 中,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 可得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
二次函数的表达式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
2
①∵
一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 与二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ),
联立关系式得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
整理得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 位于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的上方,∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 位于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的下方,同理可证.
故可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
3
方法一:
①∵
二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 图像的顶点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像的顶点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
新二次函数的图像是由原二次函数的图像向右平移 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 个单位,向上平移3个单位得到的.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的对应点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的对应点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
联立关系式可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
整理得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 时,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
②∵
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
方法二:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 平移前的对应点分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 平移前的对应点分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
由(2)②及平移的性质可知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
②∵
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴的距离为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 轴与二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像的交点,
平移后点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的对应点即为点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 图像的顶点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的图像的顶点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
新二次函数的图像是由原二次函数的图像向右平移 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 个单位,向上平移3个单位得到的.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,将点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的坐标代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 中,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
另解:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,∴ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的对应点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,∴点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的横坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> .将点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的坐标代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 中,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>

28.(1)作图见解析;交流: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,或 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
探究:正整数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 不是3的倍数),理由见解析
(2)
作图见解析

【解析】
1)由操作可知,如果 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 可以用 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的线性表示,那么该圆弧就可以被三等分
2)将圆周14等分就是把 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 所对的圆周角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 所对弧三等分即可,给出一种算法: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
1

操作:


 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
交流: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,或 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>
探究:设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 为非负整数).
或设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 为正整数).
所以对于正整数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 不是3的倍数),都可以仅用圆规将半圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 的圆心角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a> 所对的弧三等分;
2
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/558/" title="江苏" class="c1" target="_blank">江苏</a> <a href="/tags/744/" title="江苏省" class="c1" target="_blank">江苏省</a> <a href="/tags/988/" title="镇江" class="c1" target="_blank">镇江</a>