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【327676】2022年黑龙江省大庆市中考数学真题

时间:2025-01-20 19:58:19 作者: 字数:25361字
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2022年黑龙江省大庆市中考数学真题

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一、选择题

1.2022的倒数是(       
A
2022
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

2.地球上的陆地面积约为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,数字 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 用科学记数法表示为(     )
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

3.实数cd在数轴上的对应点如图所示,则下列式子正确的是(     )
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

4.下列图形中,既是轴对称图形又是中心对称图形的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

5.小明同学对数据1222364■52进行统计分析,发现其中一个两位数的个位数字被墨水污染已无法看清,则下列统计量与被污染数字无关的是(     )
A
.平均数
B
.标准差
C
.方差
D
.中位数

6.已知圆锥的底面半径为5,高为12,则它的侧面展开图的面积是(     )
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

7.如图,将平行四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 沿对角线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 折叠,使点A落在E处.若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的度数为(     )
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

8.下列说法不正确的是(     )
A
.有两个角是锐角的三角形是直角或钝角三角形
B
.有两条边上的高相等的三角形是等腰三角形
C
.有两个角互余的三角形是直角三角形
D
.底和腰相等的等腰三角形是等边三角形

9.平面直角坐标系中,点My轴的非负半轴上运动,点Nx轴上运动,满足 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .点Q为线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的中点,则点Q运动路径的长为(     )
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

10.函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 叫做高斯函数,其中x为任意实数, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 表示不超过x的最大整数.定义 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则下列说法正确的个数为(     )
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
高斯函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,x的取值范围是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
A
0
B
1
C
2
D
3

评卷人

得分




二、填空题

11.在函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,自变量 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的取值范围是_________

12.写出一个过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> yx增大而减小的一次函数关系式____________

13.满足不等式组 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的整数解是____________

14.不透明的盒中装有三张卡片,编号分别为123.三张卡片质地均匀,大小、形状完全相同,摇匀后从中随机抽取一张卡片记下编号,然后放回盒中再摇匀,再从盒中随机取出一张卡片,则两次所取卡片的编号之积为奇数的概率为____________

15.已知代数式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 是一个完全平方式,则实数t的值为____________

16.观察下列“蜂窝图”,按照这样的规律,则第16个图案中的“ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ”的个数是____________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

17.已知函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的图象与坐标轴恰有两个公共点,则实数m的值为____________

18.如图,正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,点EF分别是边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 上的两个动点,且正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的周长是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 周长的2倍,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 分别与对角线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 交于点MN.给出如下几个结论:①若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ;② <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ;③若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ;④若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .其中正确结论的序号为____________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

评卷人

得分




三、解答题

19.计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

20.先化简,再求值: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .其中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

21.某工厂生产某种零件,由于技术上的改进,现在平均每天比原计划多生产20个零件,现在生产800个零件所需时间与原计划生产600个零件所需时间相同.求现在平均每天生产多少个零件?

22.如图,为了修建跨江大桥,需要利用数学方法测量江的宽度 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .飞机上的测量人员在C处测得AB两点的俯角分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .若飞机离地面的高度 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,且点DAB在同一水平直线上,试求这条江的宽度 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> (结果精确到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,参考数据: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

23.中华文化源远流长,中华诗词寓意深广,为了传承优秀传统文化,我市某校团委组织了一次全校2000名学生参加的“中国诗词大会”海选比赛,赛后发现所有参赛学生的成绩不低于50分,为了更好地了解本次海选比赛的成绩分布情况.随机选取其中200名学生的海选比赛成绩(总分100分)作为样本进行整理,得到海选成绩统计表与扇形统计图如下:
抽取的200名学生成绩统计表

组别

海选成绩

人数

A

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

10

B

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

30

C

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

40

D

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

a

E

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

70


 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
请根据所给信息解答下列问题:
(1)
填空:① <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ____________,② <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ____________,③ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ____________度;
(2)
若把统计表每组中各个成绩用这组数据的中间值代替(例如:A组数据中间值为55分),请估计被选取的200名学生成绩的平均数;
(3)
规定海选成绩不低于90分记为“优秀”,请估计该校参加这次海选比赛的2000名学生中成绩“优秀”的有多少人?

24.如图,在四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,点EC为对角线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 上的两点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(1)
求证:四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 是平行四边形;
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

25.已知反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 和一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,其中一次函数图象过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 两点.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(1)
求反比例函数的关系式;
(2)
如图,函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的图象分别与函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 图象交于AB两点,在y轴上是否存在点P,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 周长最小?若存在,求出周长的最小值;若不存在,请说明理由.

26.果园有果树60棵,现准备多种一些果树提高果园产量.如果多种树,那么树之间的距离和每棵果树所受光照就会减少,每棵果树的平均产量随之降低.根据经验,增种10棵果树时,果园内的每棵果树平均产量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .在确保每棵果树平均产量不低于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的前提下,设增种果树x <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> x为整数)棵,该果园每棵果树平均产量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,它们之间的函数关系满足如图所示的图象.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(1)
图中点P所表示的实际意义是________________________,每增种1棵果树时,每棵果树平均产量减少____________ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(2)
yx之间的函数关系式,并直接写出自变量x的取值范围;
(3)
当增种果树多少棵时,果园的总产量 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 最大?最大产量是多少?

27.如图,已知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 外接圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的直径, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .点D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 外的一点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中点,弦 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 过点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(1)
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的切线;
(2)
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,求弦 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的长.

28.已知二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 图像的对称轴为直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .将二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 图像中y轴左侧部分沿x轴翻折,保留其他部分得到新的图像C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(1)
b的值;
(2)①
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,图像Cx轴交于点MNMN的左侧),与y轴交于点P.当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 为直角三角形时,求m的值;
在①的条件下,当图像C <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,结合图像求x的取值范围;
(3)
已知两点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,当线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 与图像C恰有两个公共点时,直接写出m的取值范围.

参考答案

1.C

【解析】
根据倒数的定义作答即可.
2022
的倒数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
故选:C

2.B

【解析】
科学记数法的表示形式为a×10n,其中1≤|a|10n为整数.确定n的值时,要看原数变成a时,小数点移动了多少位,|n|与小数点移动的位数相同.当原数的绝对值大于或等于10时,n为正整数.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 用科学记数法表示为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
故选:B.

3.C

【解析】
根据数轴上的点表示的数右边的总比左边的大,有理数的运算,绝对值的意义,可得答案.
解:由数轴上的点表示的数右边的总比左边的大,得c0d
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,原结论错误,故此选项不符合题意;
B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,原结论错误,故此选项不符合题意;
C、∵c0d,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,∴ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,原结论正确,故此选项符合题意;
D、∵c0d,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,∴ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,原结论错误,故此选项不符合题意;
故选:C

4.D

【解析】
根据中心对称图形和轴对称图形的定义,即可求解.在平面内,如果一个图形沿一条直线折叠,直线两旁的部分能够完全重合,这样的图形叫做轴对称图形;在平面内,如果把一个图形绕某个点旋转180°后,能与原图形重合,那么就说这个图形是中心对称图形.
解:A、既不是中心对称图形,又不是轴对称图形,故本选项不符合题意;
B、是轴对称图形,不是中心对称图形,故本选项不符合题意;
C、既不是中心对称图形,又不是轴对称图形,故本选项不符合题意;
D、既是轴对称图形又是中心对称图形,故本选项符合题意;
故选:D

5.D

【解析】
根据平均数,标准差,方差与中位数的定义进行判断即可.
解:A中平均数是指在一组数据中所有数据之和再除以这组数据的个数,与被污染数有关,故不符合题意;
C
中方差是每个样本值与全体样本值的平均数之差的平方和的平均数,与被污染数有关,故不符合题意;
B
中标准差是方差的算术平方根,与被污染数有关,故不符合题意;
D
中是按顺序排列的一组数据中居于中间位置的数,为36,与被污染数无关,故符合题意;
故选D

6.B

【解析】
根据圆锥侧面展开图的面积 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,计算求解即可.
解:由题意知,圆锥侧面展开图的半径即圆锥的母线长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
圆锥侧面展开图的面积为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
故选B

7.C

【解析】
先根据平行四边形的性质,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,根据平行线的性质,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,根据折叠得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,根据三角形内角和得出∠A的度数即可.
解:∵四边形ABCD为平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
根据折叠可知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,故C正确.
故选:C

8.A

【解析】
利用等腰三角形的性质与判定、等边三角形的性质与判定、直角三角形的判定,对各选项逐项分析可得出正确答案.
解:A、设∠1、∠2为锐角,
因为:∠1+∠2+∠3=180°
所以:∠3可以为锐角、直角、钝角,所以该三角形可以是锐角三角形,也可以是直角或钝角三角形,
A选项不正确,符合题意;
B
、如图,在ABC中,BEACCDAB,且BE=CD
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
BEACCDAB
∴∠
CDB=∠BEC=90°
RtBCDRtCBE中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
RtBCDRtCBEHL),
∴∠
ABC=∠ACB
AB=AC,即ABC是等腰三角形.,
B选项正确,不符合题意;
C
、根据直角三角形的判定:有两个角互余的三角形是直角三角形,,
C选项正确,不符合题意;
D
、底和腰相等的等腰三角形是等边三角形,
D选项正确,不符合题意;
故选:A

9.B

【解析】
设点M的坐标为(0m),点N的坐标为(n0),则点Q的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,然后分两种情况, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的函数关系式,即可得出Q横纵坐标的关系式,找出点Q的运动轨迹,根据勾股定理求出运动轨迹的长即可.
解:设点M的坐标为(0m),点N的坐标为(n0),则点Q的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ) ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
此时点Q在一条线段上运动,线段的一个端点在x轴的负半轴上,坐标为(-40),另一端在y轴的负半轴上,坐标为(0-4),
此时点Q的运动路径长为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
此时点Q在一条线段上运动,线段的一个端点在x轴的正半轴上,坐标为(40),另一端在y轴的负半轴上,坐标为(0-4),
此时点Q的运动路径长为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
综上分析可知,点Q运动路径的长为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,故B正确.
故选:B

10.D

【解析】
根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 表示不超过x的最大整数,即可解答.
解:① <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,故原说法错误;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,正确,符合题意;
高斯函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,x的取值范围是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,正确,符合题意;
函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,正确,符合题意;
所以,正确的结论有3个.
故选:D

11. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

【解析】
二次根式内非负,则函数有意义.
要使函数有意义,则二次根式内为非负
∴2x+3≥0
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

12.y=-x+1(答案不唯一)

【解析】
根据一次函数的性质,k0时,函数值y随自变量x的增大而减小,然后解答即可.
解:∵函数值y随自变量x的增大而减小,
设一次函数关系式为y=-x+b
把点(01)代入得,b=1
一次函数关系式为y=-x+1
故答案为:y=-x+1(答案不唯一).

13.2

【解析】
分别求出不等式组中各不等式的解集,再求出其公共解集,找出符合条件的x的整数解即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
解不等式①得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
解不等式②得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
不等式组的解集为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
不等式组的整数解为2
故答案为:2

14. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

【解析】
根据题意列表,然后找出两次卡片编号之积为奇数的可能的结果数,然后计算求解即可.
解:由题意知,列表如下:


1

2

3

1

1,1

1,2

1,3

2

2,1

2,2

2,3

3

3,1

3,2

3,3


由表可知,两次卡片编号之积有123469,卡片组合共有9种等可能的结果,其中两次卡片编号之积为奇数有139,卡片组合共有(1,1),(1,3),(3,1),(3,34种等可能的结果,
两次卡片编号之积为奇数的概率为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

15. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

【解析】
直接利用完全平方公式求解.
解:∵代数式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 是一个完全平方式,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

16.49

【解析】
根据题意可知:第1个图案中有六边形图形:1+2+1=4个,第2个图案中有六边形图形:2+3+2=7个,……由规律即可得答案.
解:∵第1个图案中有六边形图形:1+2+1=4个,
2个图案中有六边形图形:2+3+2=7个,
3个图案中有六边形图形:3+4+3=10个,
4个图案中有六边形图形:4+5+4=13个,
……
16个图案中有六边形图形:16+17+16=49个,
故答案为:49

17.1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

【解析】
函数图象与坐标轴恰有两个公共点,则分两种情况:第一种情况,函数图象过原点;第二种情况,函数图象与x轴只有一个交点,分别计算即可
当函数图象过原点时,函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的图象与坐标轴恰有两个公共点,
此时满足 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
当函数图象与x轴只有一个交点且与坐标轴y轴也有一个交点时,
此时满足 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 是,函数变为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> y轴只有一个交点,不合题意;
综上可得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,函数图象与坐标轴恰有两个公共点.
故答案为:1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

18.

【解析】
根据已知条件可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,即可判断①,进而推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,导角可得②正确,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 是直角三角形,勾股定理验证③,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,即可判断④求解.
解:∵正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的周长是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 周长的2倍,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,故①不正确;
如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的延长线上取点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 是正方形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,故②正确;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
如图,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
同理可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 对称轴, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 对称,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 是直角三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,故③不正确,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
故④不正确.
故答案为:②.

19. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

【解析】
原式分别根据绝对值的代数意义,零指数幂的运算法则以及立方根的意义化简各项后,再计算乘法,最后计算加法即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
=
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
=
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
=
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

20. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

【解析】
根据分式的减法和除法可以化简题目中的式子,然后将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 代入化简后的式子即可解答本题.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
=
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
=
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
=
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
=
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,原式= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

21.现在平均每天生产80个零件

【解析】
设现在平均每天生产 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 个零件,则原计划生产 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 个零件,由题意得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,计算求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的值,然后进行检验即可.
解:设现在平均每天生产 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 个零件,则原计划生产 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 个零件,
由题意得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
去分母得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
移项合并得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
系数化为1得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
检验,将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 代入得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,所以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 是原分式方程的解,
现在平均每天生产 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 个零件.

22.这条江的宽度AB约为732

【解析】
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,利用锐角三角函数,用 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 表示出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的长,然后计算出AB的长;
解:如图,∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 米,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> (米),
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> (米) ,
答:这条江的宽度AB约为732米.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

23.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

【解析】
1)结合统计表和扇形统计图计算即可;
2)利用加权平均数公式计算即可;
3)直接用总人数乘以样本的优秀率即可求解.
(1)
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> (人);
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(2)
被选取的200名学生成绩的平均数为:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
答:估计被选取的200名学生成绩的平均数是82
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> (人).
答:估计该校参加这次海选比赛的2000名学生中成绩“优秀”的有700人.

24.(1)证明见解析
(2)
证明见解析

【解析】
1)由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,进而结论得证;
2)由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,进而结论得证.
(1)
证明:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 是平行四边形.
(2)
证明:由(1)知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

25.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

【解析】
1)用待定系数法求出函数解析式;
2)作点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴的对称点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,进行计算即可;
(1)
解:把 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,得
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
解得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
所以反比例函数解析式是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(2)
存在点P使△ABP周长最小,理由:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 得,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
作点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴的对称点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,当点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 在一条直线上时,线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的长度最短,所以存在点P使△ABP周长最小,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
ABP的周长= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

26.(1)增种28棵果树时,每棵果树的平均产量为66kg0.5
(2)
yx的函数关系式为y=-0.5x+80(0x≤80)
(3)
增种果树50棵时,果园的总产量最大,最大产量是6050kg

【解析】
(1)①
根据图像可知,增种果树为x <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> x为整数)棵,该果园每棵果树平均产量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,可以得出图中点P表示的实际意义;②根据增种10棵果树时,果园内的每棵果树平均产量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .增种28棵果树时,每棵果树的平均产量为66kg,可以得出每增种1棵果树时,每棵果树平均产量减少的量;
(2)
根据增种10棵果树时,果园内的每棵果树平均产量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .增种28棵果树时,每棵果树的平均产量为66kg,设yx的函数关系式为y=kx+b,将x=10y=75x=28y=66代入可得yx的函数关系式;
(3)
根据题意,果园的总产量w=每棵果树平均产量 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ×果树总棵树;可得wx的二次函数关系式,根据二次函数的图像和性质即可解得.
1)①根据图像可知,设增种果树x <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> x为整数)棵,该果园每棵果树平均产量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,所以图中点P表示的实际意义是:增种28棵果树时,每棵果树的平均产量为66kg,所以答案为:增种28棵果树时,每棵果树的平均产量为66kg,②根据增种10棵果树时,果园内的每棵果树平均产量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .增种28棵果树时,每棵果树的平均产量为66kg,可以得出:每增种1棵果树时,每棵果树平均产量减少为:(75-66)÷28-10=9÷18=0.5kg)所以答案为:0.5
2)根据增种10棵果树时,果园内的每棵果树平均产量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> .增种28棵果树时,每棵果树的平均产量为66kg,设yx的函数关系式为y=kx+bx=10y=75x=28y=66代入可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> yx的函数关系式为y=-0.5x+80(0x≤80)
3)根据题意,果园的总产量w=每棵果树平均产量 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ×果树总棵树可得w=(-0.5x+80)(60+x)=-0.5x2+50x+4800∵a=-0.50所以当x= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,w有最大值w最大=6050所以增种果树50棵时,果园的总产量最大,最大产量是6050kg

27.(1)答案见解析
(2)
答案见解析
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

【解析】
1)根据BC是△ABC外接圆⊙O的直径,得∠BAC=90°,由因为∠ACD=∠B,得∠BCD=90°,即可得答案;
2)先证△FEA∽△CEG,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,又因为AE=CEEF=2EG,得CE2=2EG2,得OC2-OE2=EC2,即可得答案;
3)作ONFG,延长FG交线段于点W,得四边形ONWC为矩形,得NG=1.5EGNE=0.5EGEW=8-1.5EG+EG=8-0.5EG,得(8-0.5EG2+64-2EG2- <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> EG2=2EG2,得EG= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,即可得答案.
(1)
解:∵BC是△ABC外接圆⊙O的直径,
∴∠
BAC=90°
∴∠
B+∠ACB=90°
∵∠
ACD=∠B
∴∠
ACD+∠ACB=90°
∴∠
BCD=90°
OC OO 的半径,
CD OO 的切线;
(2)
如下图,连接AFCG
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
∴∠
AFE=∠ECG
∵∠
AEF=∠CEG
∴△
FEA∽△CEG
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
EAC中点,
AE=CE
EF=2EG
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>    
CE2=2EG2
∵∠
BAC=90°,点EAC中点,
EO <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> AB
∴∠
OEC=90°
OC2-OE2=EC2
OC2-OE2=2EG2
OC+OE)(OCOE=EGEF
(3)
ONFG,延长FG交线段于点W
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
BC=16
OC=8
FG <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> BC
四边形ONWC为矩形,
EF=2EG
FG=3EG
NG=1.5EGNE=0.5EGEW=8-1.5EG+EG=8-0.5EG
由(2)可知:OC2-OE2=2EG2
CE2=2EG2   
OE2=64-2EG2ON2=64-2EG2- <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> EG2EW2=8-0.5EG2
8-0.5EG2+64-2EG2- <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> EG2=2EG2
解得EG= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
FG=3EG= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

28.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(2)①
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,② <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>

【解析】
1)根据二次函数的对称轴为直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 值即可;
2)①由(1)知,二次函数的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,令 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,令 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,整理得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,求出满足要求的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的值即可;②由①可知,二次函数解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴左侧图像的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,可画图像C如图所示,令 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,求出满足要求的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 值,令 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,求出满足要求的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 值,然后结合图求x的取值范围即可;
3)由题意知,二次函数的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 为平行于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴的线段,由题意知,分两种情况求解:①当线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 与图像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴左侧有一个交点时,线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 与图像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴右侧有一个交点,即令 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的取值范围求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的取值范围,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的取值范围求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的取值范围,然后取公共部分即可;②当线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 与图像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴左侧没有交点,线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 与图像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴右侧有两个交点,即令 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的取值范围求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的取值范围,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的取值范围求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的取值范围,然后取公共部分即可.
(1)
解:由题意知,二次函数的对称轴为直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的值为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(2)
解:由(1)知,二次函数的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,或 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 为直角三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
整理得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,或 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> (不合题意,舍去),
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的值为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
解:由①可知,二次函数解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>                     
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴左侧图像的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴的交点坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
图像C如下所示,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,或 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> (不合题意,舍去),
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,或 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
由图像可知求x的取值范围为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
(3)
解:由题意知,二次函数的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 为平行于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴的线段,
由线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 与图像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 恰有两个公共点可知,①当线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 与图像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴左侧有一个交点时,线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 与图像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴右侧有一个交点,即令 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
当线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 与图像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴左侧没有交点,线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 与图像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 轴右侧有两个交点,即令 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> ,有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>
综上所述, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a> 的取值范围为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/973/" title="黑龙江省" class="c1" target="_blank">黑龙江省</a> <a href="/tags/974/" title="大庆" class="c1" target="_blank">大庆</a> <a href="/tags/1102/" title="黑龙江" class="c1" target="_blank">黑龙江</a>