当前位置:首页 > 中考 > 数学试卷

【327885】2023年四川省眉山市中考数学真题

时间:2025-01-20 20:35:02 作者: 字数:19121字
简介:

绝密·启用前

2023年四川省眉山市中考数学真题

题号

总分

得分





注意事项:

1.答题前填写好自己的姓名、班级、考号等信息

2.请将答案正确填写在答题卡上



评卷人

得分




一、选择题

1. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的倒数是( )
A
-2
B
2
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

2.生物学家发现了某种花粉的直径约为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 毫米,数据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 用科学记数法表示正确的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

3.下列运算中,正确的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

4.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的度数为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

5.已知一组数据为23456,则该组数据的方差为(       
A
2
B
4
C
6
D
10

6.关于x的一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 有两个不相等的实数根,则m的取值范围是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

7.已知关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的二元一次方程组 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解满足 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则m的值为(       
A
0
B
1
C
2
D
3

8.由相同的小正方体搭成的立体图形的部分视图如图所示,则搭成该立体图形的小正方体的最少个数为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
A6
B
9
C
10
D
14

9.关于x的不等式组 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的整数解仅有4个,则m的取值范围是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

10.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点B,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点C <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点D,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的度数为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

11.如图,二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的图象与x轴的一个交点坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,对称轴为直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,下列四个结论:① <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ;② <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ;③ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ;④当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ;其中正确结论的个数为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
A1
B
2
C
3
D
4

12.如图,在正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中,点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 上一点,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 至点F,使 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,连结 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点K,过点A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,垂足为点H,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点G,连结 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 下列四个结论:① <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ;② <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ;③ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ;④ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> .其中正确结论的个数为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>           
A1
B
2
C
3
D
4

评卷人

得分




二、填空题

13.分解因式: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> __

14.已知方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的根为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的值为____________

15.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是中线,分别以点A,点B为圆心,大于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 长为半径作弧,两孤交于点MN.直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点E连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点F.过点D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点G.若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的长为____________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

16.关于x的方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解为非负数,则m的取值范围是____________

17.一渔船在海上A处测得灯塔C在它的北偏东60°方向,渔船向正东方向航行12海里到达点B处,测得灯塔C在它的北偏东45°方向,若渔船继续向正东方向航行,则渔船与灯塔C的最短距离是____________海里.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

18.如图,在平面直角坐标系 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中,点B的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,过点B分别作x轴、y轴的垂线,垂足分别为点C、点A直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 交于点D.与y轴交于点E.动点M在线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 上,动点N在直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 上,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是以点N为直角顶点的等腰直角三角形,则点M的坐标为________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

评卷人

得分




三、解答题

19.计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

20.先化简: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,再从 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 选择中一个合适的数作为x的值代入求值.

21.某校为落实“双减”工作,推行“五育并举”,计划成立五个兴趣活动小组(每个学生只能参加一个活动小组):A.音乐,B.美术,C.体育,D.阅读,E.人工智能,为了解学生对以上兴趣活动的参与情况,随机抽取了部分学生进行调查统计,并根据统计结果,绘制成了如图所示的两幅不完整的统计图:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
根据图中信息,完成下列问题:
(1)①
补全条形统计图(要求在条形图上方注明人数);
扇形统计图中的圆心角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的度数为____________
(2)
若该校有3600名学生,估计该校参加E组(人工智能)的学生人数;
(3)
该学校从E组中挑选出了表现最好的两名男生和两名女生,计划从这四位同学中随机抽取两人参加市青少年人工智能竞赛,请用画树状图或列表的方法求出恰好抽到一名男生一名女生的概率.

22.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中,点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中点,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 并延长交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的延长线于点F
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>       
(1)求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(2)
G是线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 上一点,满足 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点H,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的长.

23.习近平总书记说:“读书可以让人保持思想活力,让人得到智慧启发,让人滋养浩然正气.”某校为提高学生的阅读品味,现决定购买获得矛盾文学奖的甲、乙两种书共100本,已知购买2本甲种书和1本乙种书共需100元,购买3本甲种书和2本乙种书共需165元.
(1)
求甲,乙两种书的单价分别为多少元:
(2)
若学校决定购买以上两种书的总费用不超过3200元,那么该校最多可以购买甲种书多少本?

24.如图,在平面直角坐标系 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中,直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> x轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,与y轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 在第四象限内的图象交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
(1)求反比例函数的表达式:
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时,直接写出x的取值范围;
(3)
在双曲线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 上是否存在点P,使 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是以点A为直角顶点的直角三角形?若存在,求出点P的坐标;若不存在,请说明理由.

25.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中,以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 为直径的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,过点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点D,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的延长线于点P
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
(1)求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的切线;
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的长.

26.在平面直角坐标系中,已知抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> x轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 两点,与y轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,点P是抛物线上的一个动点.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
(1)求抛物线的表达式;
(2)
当点P在直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 上方的抛物线上时,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点D.如图1.当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的值最大时,求点P的坐标及 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的最大值;
(3)
过点Px轴的垂线交直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点M,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 沿直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 翻折,当点M的对应点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 恰好落在y轴上时,请直接写出此时点M的坐标.

参考答案

1.A

【解析】
根据倒数的概念求解即可.
根据乘积等于1的两数互为倒数,可直接得到- <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的倒数为-2
故选:A

2.A

【解析】
根据用科学记数法可以把一个绝对值小于1的非零数表示成 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,其中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> n是一个负整数,n的绝对值等于原数中的第一个非零数字前面所有零的个数(包括小数点前面的那个零),即可解答.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选:A

3.D

【解析】
根据合并同类项可判断A,根据完全平方公式可判断B,根据单项式除以单项式可判断C,根据积的乘方与幂的乘方运算可判断D,从而可得答案.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 不是同类项,不能合并,故A不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,故B不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,故C不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,故D符合题意;
故选D

4.C

【解析】
根据等腰三角形的等边对等角和三角形的内角和定理,即可解答.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选:C

5.A

【解析】
先计算这组平均数的平均数,再根据方差公式计算即可.
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选A

6.D

【解析】
利用一元二次方程根的判别式求解即可.
解:∵关于x的一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 有两个不相等的实数根,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选D

7.B

【解析】
将方程组的两个方程相减,可得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即可解答.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选:B

8.B

【解析】
根据俯视图可得底层最少有6个,再结合左视图可得第二层最少有2个,即可解答.
解:根据俯视图可得搭成该立体图形的小正方体第三层最少为6个,
根据左视图第二层有2个,可得搭成该立体图形的小正方体第二层最少为2个,
根据左视图第三层有1个,可得搭成该立体图形的小正方体第三层最少为1个,
故搭成该立体图形的小正方体最少为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 个,
故选:B

9.A

【解析】
不等式组整理后,表示出不等式组的解集,根据整数解共有4个,确定出m的范围即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
由②得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解集为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
由不等式组的整数解只有4个,得到整数解为210 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选:A

10.C

【解析】
如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,从而可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解:如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选C

11.D

【解析】
根据二次函数开口向上,与y轴交于y轴负半轴, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,根据对称轴为直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,由此即可判断①;求出二次函数与x轴的另一个交点坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,进而得到当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,由此即可判断②;根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即可判断③;利用图象法即可判断④.
解:∵二次函数开口向上,与y轴交于y轴负半轴,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
二次函数的对称轴为直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,故①正确;
二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的图象与x轴的一个交点坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的图象与x轴的另一个交点坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,故②正确;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,故③正确;
由函数图象可知,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,故④正确;
综上所述,其中正确的结论有①②③④共4个,
故选D

12.C

【解析】
根据正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的性质可由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 定理证 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即可判定 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是等腰直角三角形,进而可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,由直角三角形斜边中线等于斜边一半可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ;由此即可判断①正确;再根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可判断③正确,进而证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,结合 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即可得出结论④正确,由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 随着 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 长度变化而变化,不固定,可 判断② <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 不一定成立.
解:∵正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是等腰直角三角形,  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,故①正确;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>           
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> , <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,故③正确,
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,故④正确,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
而点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 上一动点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 随着 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 长度变化而变化,不固定,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
则故 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 不一定成立,故②错误;
综上,正确的有①③④共3个,
故选:C

13. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
先提取公因式,再利用完全平方公式进行因式分解即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

14.6

【解析】
解方程,将解得的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 即可解答.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
对左边式子因式分解,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
可得原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故答案为:6

15. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
由作图方法可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的垂直平分线,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中线,进而得到点F <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的重心,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,利用相似三角形的性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解:由作图方法可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的垂直平分线,
E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中线,
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中线,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 交于点F
F <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的重心,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

16. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
解分式方程,可用 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 表示 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,再根据题意得到关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的一元一次不等式即可解答.
解:解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解为非负数,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的取值范围是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

17. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ## <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,利用特殊角的三角函数值,列方程即可解答.
解:如图,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
由题意可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> , <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> x
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可得方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 渔船与灯塔C的最短距离是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 海里,
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

18. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
如图,由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是以点N为直角顶点的等腰直角三角形,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 在以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 为直径的圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 上, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 与直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的交点,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 重合时,符合题意,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,当N <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的上方时,如图,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 轴于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,而 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,再解方程可得答案.
解:如图,∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是以点N为直角顶点的等腰直角三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 在以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 为直径的圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 上, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 与直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的交点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 重合时,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,符合题意,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
N <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的上方时,如图,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 轴于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
综上: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

19.6

【解析】
先计算零指数幂,负整数指数幂和特殊角三角函数值,再根据实数的混合计算法则求解即可.
解:原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

20. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 1

【解析】
先根据分式混合运算法则进行计算,然后再代入数据求值即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 代入得:原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

21.(1)①补全图形见解析;② <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 人;
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
1)①先求解总人数,再求解D组人数,再补全统计图即可;②由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 乘以D组的占比即可得到圆心角的大小;
2)由3600乘以E组人数的占比即可;
3)画出树状图,数出所有的情况数和符合题意的情况数,再根据概率公式,即可求解.
1)解:①由题意可得:总人数为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> (人),
D组人数为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> (人),
补全图形如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
由题意可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
2)该校有3600名学生,估计该校参加E组(人工智能)的学生人数有:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> (人);
3)记AB表示男生,CD表示女生,画树状图如图:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
共有12种等可能的结果,其中抽到一名男生一名女生的有8种结果,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

22.(1)见解析
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
1)根据平行四边形的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即可解答;
2)通过平行四边形的性质证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,再通过(1)中的结论得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,最后证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,利用对应线段比相等,列方程即可解答.
1)证明: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
2)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> , <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
可得方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的长为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

23.(1)甲种书的单价为35元,乙种书的单价为30
(2)
该校最多可以购买甲种书40

【解析】
1)设甲种书的单价为x元,乙种书的单价为y元,利用2本甲种书的价格 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 1本乙种书的价格 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 3本甲种书的价格 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 2本乙种书的价格 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,列方程解答即可;
2)设购买甲种书 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 本,则购买乙种书 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 本,根据购买甲种书的总价 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 购买乙种书的总价 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,列不等式解答即可.
1)解:设甲种书的单价为x元,乙种书的单价为y元,
可得方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 原方程的解为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
答:甲种书的单价为35元,乙种书的单价为30元.
2)解:设购买甲种书 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 本,则购买乙种书 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 本,
根据题意可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故该校最多可以购买甲种书40本,
答:该校最多可以购买甲种书40本.

24.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
1)将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,求得一次函数表达式,进而可得点C的坐标,再将点C的坐标代入反比例函数即可;
2)将一次函数与反比例函数联立方程组,求得交点坐标即可得出结果;
3)过点A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> y轴于点M,勾股定理得出点M的坐标,在求出直线AP的表达式,与反比例函数联立方程组即可.
1)解:把 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
反比例函数的表达式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
2)解:联立 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
一次函数与反比例函数的两个交点坐标分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
由函数图象可知,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时,一次函数图象在反比例函数图象上方,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
3)解:如图所示,设直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> y轴于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是以点A为直角顶点的直角三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
同理可得直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
联立 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
P的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

25.(1)见解析
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
1)连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,利用角平分线的性质和等边对等角,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即可解答;
2)根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的长,再利用勾股定理得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的长,即可得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的长,最后证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即可解答.
1)证明:如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的切线;
2)解:设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
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/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

26.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(2)
P的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的最大值为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(3)
M的坐标为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
1)利用待定系数法求出抛物线的解析式即可;
2)过点P <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 轴,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点Q,求出直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,设点P的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 轴,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,求出点P的坐标和最大值即可;
3)证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,根据当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时,点PMC <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 四点重合,不存在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 舍去,求出点M的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
1)解:把 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</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/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
2)解:过点P <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 轴,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点Q,如图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>       
设直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,把 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 代入得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
设点P的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
P在直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 上方的抛物线上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 轴,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 有最大值 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
此时点P的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
3)解:根据折叠可知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 轴,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
整理得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时,点PMC <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 四点重合,不存在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
M的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1076/" title="眉山" class="c1" target="_blank">眉山</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>