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【327731】2022年辽宁省锦州市中考数学真题

时间:2025-01-20 20:06:16 作者: 字数:21088字
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2022年辽宁省锦州市中考数学真题

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得分




一、选择题

1.﹣2022的绝对值是(  )
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
C
2022
D
.﹣2022

2.党的十八大以来,以习近平同志为核心的党中央重视技能人才的培育与发展.据报道,截至2021年底,我国高技能人才超过60000000人,请将数据60000000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/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

3.如图所示的几何体是由4个完全相同的小正方体搭成的,它的主视图是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

4.某校教师自愿者团队经常做公益活动,下表是对10名成员本学期参加公益活动情况进行的统计:

次数/

10

8

7

4

人数

3

4

2

1


那么关于活动次数的统计数据描述正确的是(       
A
.中位数是8,平均数是8
B
.中位数是8,众数是3
C
.中位数是3,平均数是8
D
.中位数是3,众数是8

5.下列运算正确的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

6.如图,直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,将含 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 角的直角三角板 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 按图中位置摆放,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的度数为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

7.如图,在矩形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,分别以点AC为圆心,以大于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的长为半径作弧,两弧相交于点MN,作直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 分别交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点EF,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的长为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

8.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,动点P从点A出发,以每秒1个单位长度的速度沿线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 匀速运动,当点P运动到点B时,停止运动,过点P <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点Q,将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 沿直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 折叠得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,设动点P的运动时间为t秒, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 重叠部分的面积为S,则下列图象能大致反映St之间函数关系的是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

评卷人

得分




二、填空题

9.甲、乙两名学生10次立定跳远成绩的平均数相同,若甲生10次立定跳远成绩的方差为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,乙生10次立定跳远成绩的方差为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,则甲、乙两名学生10次立定跳远成绩比较稳定的是___________.(填“甲”或“乙”)

10.在一个不透明的口袋中装有红球和白球共8个,这些球除颜色外都相同,将口袋中的球搅匀后,从中随机摸出一个球,记下它的颜色后再放回口袋中,不断重复这一过程,共摸了100次球,发现有75次摸到红球,则口袋中红球的个数约为___________

11.若关于x的一元二次方程x2+3x+k=0有两个不相等的实数根,则k的取值范围是_____

12.如图,四边形ABCD内接于⊙OAB为⊙O的直径,∠ADC=130°,连接AC,则∠BAC的度数为___________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

13.如图,在正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中,E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的中点,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点F.若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的面积为___________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

14.如图,在平面直角坐标系中,AOB的边OBy轴上,边ABx轴交于点D,且BD=AD,反比例函数y= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> (x0)的图像经过点A,若SOAB=1,则k的值为___________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

15.如图,抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> x轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 和点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,以下结论:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ;② <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ;③ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ;④当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 时,yx的增大而减小.其中正确的结论有___________.(填写代表正确结论的序号)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

16.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 为射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 上一点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 为射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 上一点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> .以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 为边在其右侧作菱形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 与射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ;延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 交射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 为边在其右侧作菱形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 与射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ;延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 交射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 为边在其右侧作菱形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 与射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ;…,按此规律进行下去,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的面积___________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

评卷人

得分




三、解答题

17.先化简,再求值: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,其中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

18.某校为了传承中华优秀传统文化,举行“薪火传承育新人”系列活动,组建了四个活动小组:A(经典诵读),B(诗词大赛),C(传统故事),D(汉字听写).学校规定:每名学生必须参加且只能参加其中一个小组.学校随机抽取了部分学生,对其参加活动小组的情况进行了调查.下面图1和图2是根据调查结果绘制的不完整的统计图.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
请根据图中提供的信息,解答下列问题:
(1)
本次随机调查的学生有___________名,在扇形统计图中“C部分圆心角的度数为___________
(2)
通过计算补全条形统计图;
(3)
若该校共有1500名学生,请根据以上调查结果,估计参加“B活动小组的人数.

19.小华同学从一副扑克牌中取出花色为“红心”,“黑桃”,“方块”,“梅花”各1张放入不透明的甲盒中,再从这副扑克牌中取出花色为“红心”,“黑桃”,“方块”,“梅花”各1张放入不透明的乙盒中.
(1)
小华同学从甲盒中随机抽取1张,抽到扑克牌花色为“红心”的概率为___________
(2)
小华同学从甲、乙两个盒中各随机抽取1张扑克牌.请用画树状图或列表的方法,求抽到扑克牌花色恰好是1张“红心”和1张“方块”的概率.

20.2022323日“天官课堂”第二课在中国空间站开讲了,精彩的直播激发了学生探索科学奥秘的兴趣.某中学为满足学生的需求,充实物理兴趣小组的实验项目,决定购入AB两款物理实验套装,其中A款套装单价是B款套装单价的1.2倍,用9900元购买的A款套装数量比用7500元购买的B款套装数量多5套.求AB两款套装的单价分别是多少元.

21.如图,一艘货轮在海面上航行,准备要停靠到码头C,货轮航行到A处时,测得码头C在北偏东60°方向上.为了躲避AC之间的暗礁,这艘货轮调整航向,沿着北偏东30°方向继续航行,当它航行到B处后,又沿着南偏东70°方向航行20海里到达码头C.求货轮从AB航行的距离(结果精确到0.1海里.参考数据:sin50°≈0.766cos50°≈0.643tan50°≈1.192).
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

22.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的直径,点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 上,D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的中点,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 并延长交于点C.连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的延长线上取一点F,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,使 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
(1)
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的切线;
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的半径.

23.某文具店购进一批单价为12元的学习用品,按照相关部门规定其销售单价不低于进价,且不高于进价的1.5倍,通过分析销售情况,发现每天的销售量y(件)与销售单价x(元)满足一次函数关系,且当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ;当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
(1)
yx之间的函数关系式;
(2)
这种学习用品的销售单价定为多少时,每天可获得最大利润,最大利润是多少元?

24.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> DEF分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的中点,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>    <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>    <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
(1)
如图1,求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
(2)
如图2,将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 绕点D顺时针旋转一定角度,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,当射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点G,射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点N时,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 并延长交射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点M,判断 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的数量关系,并说明理由;
(3)
如图3,在(2)的条件下,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 时,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的长.

25.如图,抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> x轴于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,交y轴于点C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
(1)
求抛物线的表达式;
(2)
D是直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 上方抛物线上一动点,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点N,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的值最大时,求点D的坐标;
(3)
P为抛物线上一点,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,过点P <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 交抛物线对称轴于点Q,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 时,请直接写出点P的横坐标.

参考答案

1.C

【解析】
根据绝对值的意义可直接得出答案.
解:2022的绝对值是2022
故选:C

2.B

【解析】
科学记数法的表示形式为a×10n的形式,其中1≤|a|10n为整数.确定n的值时,要看把原数变成a时,小数点移动了多少位,n的绝对值与小数点移动的位数相同.当原数绝对值大于或等于10时,n是正整数;当原数的绝对值小于1时,n是负整数.
解:将数据60000000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/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
故选B

3.C

【解析】
根据几何体的三视图可直接进行排除选项.
解:由题意得:
该几何体的主视图为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
故选C

4.A

【解析】
由表格可直接进行求解.
解:由表格得:次数为8的人数有4人,故众数为8,这组数据的中位数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,平均数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
故选A

5.B

【解析】
分别根据幂的乘方运算法则,同底数幂的乘法法则,同底数幂的除法法则以及合并同类项逐一判断即可.
解:A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,故本选项不合题意;
B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,故本选项符合题意;
C <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,故本选项不合题意;
D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,故本选项不合题意.
故选:B

6.C

【解析】
如图,根据平行线的性质可得∠3=∠1=110°,则有∠4=70°,然后根据三角形外角的性质可求解.
解:如图,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
∴∠3=∠1=110°

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
故选C

7.D

【解析】
根据矩形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 为直角三角形,根据勾股定理可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的长度,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,又由题知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的垂直平分线,于是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,于是在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中,利用锐角三角函数即可求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的长.
解:设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的交点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 为矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 为直角三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
又由作图知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的垂直平分线,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
故选:D

8.D

【解析】
由题意易得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,则有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,进而可分当点PAB中点的左侧时和在AB中点的右侧时,然后分类求解即可.
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
由题意知: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
由折叠的性质可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
当点PAB中点重合时,则有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
当点PAB中点的左侧时,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 重叠部分的面积为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
当点PAB中点的右侧时,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,如图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
由折叠性质可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 重叠部分的面积为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
综上所述:能反映 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 重叠部分的面积St之间函数关系的图象只有D选项;
故选D

9.

【解析】
根据方差可直接进行求解.
解:由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 可知: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,且甲、乙两名学生10次立定跳远成绩的平均数相同,所以甲、乙两名学生10次立定跳远成绩比较稳定的是乙;
故答案为乙.

10.6

【解析】
用球的总个数乘以摸到红球的频率即可.
解:估计这个口袋中红球的数量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> =6(个).
故答案为:6

11.k <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

【解析】
解:由题意得:=9﹣4k0
解得:k <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
故答案为:k <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

12.40°##40

【解析】
首先利用圆内接四边形的性质和∠ADC的度数求得∠B的度数,然后利用直径所对的圆周角是直角确定∠ACB=90°,然后利用直角三角形的两个锐角互余求得答案即可.
解:∵四边形ABCD内接与⊙O,∠ADC=130°
∴∠
B=180°-∠ADC=180°-130°=50°
AB为直径,
∴∠
ACB=90°
∴∠
CAB=90°-∠B=90°-50°=40°
故答案为:40°

13.3

【解析】
由正方形的性质可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,则有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,然后可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,进而问题可求解.
解:∵四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 是正方形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
故答案为3

14.2

【解析】
A x轴的垂线与x 轴交于C ,证明ADCBDO,推出SOAC = SOAB=1,由此即可求得答案.
解:设A(ab) ,如图,作A x轴的垂线与x 轴交于C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
则:AC=b OC=a ACOB
∴∠
ACD=∠BOD=90°,∠ADC=∠BDO
ADCBDO
SADC=SBDO
SOAC=SAOD+ SADC=SAOD+ SBDO= SOAB=1
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ×OC×AC= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ab=1
ab=2
A(ab) y= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 上,
k=ab=2
故答案为:2

15.①②##②①

【解析】
根据二次函数的对称轴位置和抛物线开口方向确定①③,根据x-2时判定②,由抛物线图像性质判定④

解:抛物线的对称轴在y轴右侧,则ab0,而c0,故abc0,故正确;
x-2时,函数值小于0,则4a-2b+c0,故正确;
x轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 和点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 则对称轴 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,故 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,故③错误
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 时,图像位于对称轴左边,yx的增大而减大.④错误
综上所述,正确的为①②
故答案为:①②

16. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

【解析】
过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点D,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,分别作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,然后根据菱形的性质及题意可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,则有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,进而可得出规律进行求解.
解:过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 于点D,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,分别作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,如图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
菱形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 是等边三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
同理可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
由上可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
故答案为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

17. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

【解析】
先对分式进行化简,然后再代入求解即可.
解:原式= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
=
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
=
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
=
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 代入得:原式= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

18.(1)50108°
(2)
见解析
(3)
估计参加“B活动小组的人数约有150名.

【解析】
1)由A的人数及其所占百分比可得总人数,根据各类型人数之和等于总人数求得C的人数,用360°乘以C人数所占比例即可得其对应圆心角度数;
2)据(1)的数据补全图形即可得;
3)总人数乘以B活动小组人数和所占比例即可;
1
解:本次调查的总人数为10÷20%=50(名),
C活动小组人数为50-10+5+20=15(名),
扇形统计图中,C所对应的扇形的圆心角度数是360°× <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> =108°
故答案为:50108°
2
解:由(1)得C活动小组人数为15名,
补全图形如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
3
解:估计参加“B活动小组的人数有1500× <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> =150(名).

19.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

【解析】
1)先求出从甲盒中随机抽取1张有4种等可能的结果,抽到扑克牌花色为“红心”结果只有1种,再利用概率公式求解;
2)先列出表,进而得到从甲、乙两个盒中各随机抽取1张扑克牌共有16种等可能的结果,其中抽到扑克牌花色恰好是1张“红心”和1张“方块”的结果有2种,利用概率公式求解.
1
解:根据题意可知
从甲盒中随机抽取1张有4种等可能的结果,抽到扑克牌花色为“红心”结果只有1种,
所以抽到扑克牌花色为“红心”的概率为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
2
解:列表如下:


红心

黑桃

方块

梅花

红心

红心,红心

黑桃,红心

方块,红心

梅花,红心

黑桃

红心,黑桃

黑桃,黑桃

方块,黑桃

梅花,黑桃

方块

红心,方块

黑桃,方块

方块,方块

梅花,方块

梅花

红心,梅花

黑桃,梅花

方块,梅花

梅花,梅花


从图中可知,从甲、乙两个盒中各随机抽取1张扑克牌共有16种等可能的结果,其中抽到扑克牌花色恰好是1张“红心”和1张“方块”的结果有2种,
所以抽到扑克牌花色恰好是1张“红心”和1张“方块”的概率是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

20.A款套装的单价是180元、B款套装的单价是150元.

【解析】
B款套装的单价是x元,则A款套装的单价是1.2x元,即可得出关于x的分式方程,解之经检验后即可得出结论.
解:设B款套装的单价是x元,则A款套装的单价是1.2x元,
由题意得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
解得:x=150
经检验,x=150是原方程的解,且符合题意,
∴1.2
x=180
答:A款套装的单价是180元、B款套装的单价是150元.

21.货轮从AB航行的距离约为30.6海里.

【解析】
BBDACD,在RtBCD中,利用正弦函数求得BD=15.32海里,再在RtABD中,利用含30度角的直角三角形的性质即可求解.
解:过BBDACD
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
由题意可知∠ABE=30°,∠BAC=30°,则∠C=180°-30°-30°-70°=50°
RtBCD中,∠C=50°BC=20(海里)
BD= BCsin50°≈20×0.766=15.32(海里)
RtABD中,∠BAD=30°BD=15.32(海里)
AB=2BD=30.64≈30.6(海里)
答:货轮从AB航行的距离约为30.6海里.

22.(1)证明见解析;
(2)3


【解析】
1)连接AD,由圆周角定理可得∠ADB=90°,由等弧对等角可得∠BAD=∠CAD= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> BAC,再进行等量代换可得∠ABF=90°便可证明;
2)连接ADBE,由圆周角定理可得∠AEB=90°,∠BOD=2∠BAD,于是∠BOD=∠BAC,由△OBF∽△AEB可得OBAE=OFAB,再代入求值即可;
1
证明:如图,连接AD
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
AB是圆的直径,则∠ADB=90°
D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的中点,则∠BAD=∠CAD= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> BAC
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
∴∠
CBF=∠BAD
∵∠
BAD+∠ABD=90°
∴∠
ABF=∠ABD+∠CBF=90°
ABBF
BF是⊙O的切线;
2
解:如图,连接ADBE
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
AB是圆的直径,则∠AEB=90°
∵∠
BOD=2∠BAD,∠BAC=2∠BAD
∴∠
BOD=∠BAC
又∵∠ABF=∠AEB=90°
∴△
OBF∽△AEB
OBAE=OFAB
OB∶4= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ∶2OBOB2=9
OB0,则OB=3
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的半径为3

23.(1)yx之间的函数关系式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
(2)
这种学习用品的销售单价定为16元时,每天可获得最大利润,最大利润是160元.

【解析】
1)设yx之间的函数关系式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,然后代值求解即可;
2)设每天获得的利润为w元,由(1)可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,进而根据二次函数的性质可求解.
1
解:设yx之间的函数关系式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,由题意得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
yx之间的函数关系式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
2
解:设每天获得的利润为w元,由(1)可得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,且-100
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 时,w有最大值,最大值为160
答:这种学习用品的销售单价定为16元时,每天可获得最大利润,最大利润是160元.

24.(1)见解析
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,理由见解析
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

【解析】
1)连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,根据直角三角形斜边上的中线等于斜边的一半可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,根据中位线定理可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,即可得证;
2)证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,根据(1)的结论即可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
3)连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,勾股定理求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,进而求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,根据(2)的结论 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,即可求解.
1
证明:如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> DEF分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
2
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,理由如下,
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,如图,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> DEF分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 是平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 绕点D顺时针旋转一定角度,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
3
如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

25.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
(3)
P的横坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>

【解析】
1)把点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 代入解析式求解即可;
2)过点DDHy轴,交AC于点H,由(1)设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,直线AC的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,然后可求出直线AC的解析式,则有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,进而可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,最后根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 可进行求解;
3)由题意可作出图象,设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,然后根据题意及k型相似可进行求解.
1
解:把点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 代入得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
抛物线的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
2
解:过点DDHy轴,交AC于点H,如图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,直线AC的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
由(1)可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
直线AC的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
DHy轴,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 的值最大,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
3
解:由题意可得如图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
分别过点CQ作垂线,交过点Py轴的平行线于点GH
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
设点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> ,由题意可知:抛物线的对称轴为直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 时,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a> 时,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>
综上:点P的横坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/990/" title="辽宁省" class="c1" target="_blank">辽宁省</a> <a href="/tags/1056/" title="锦州" class="c1" target="_blank">锦州</a> <a href="/tags/1122/" title="辽宁" class="c1" target="_blank">辽宁</a>