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【327887】2023年四川省内江市中考数学真题

时间:2025-01-20 20:35:13 作者: 字数:20447字
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2023年四川省内江市中考数学真题

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得分




一、选择题

1.-2的绝对值是(     
A
2
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

2.作为世界文化遗产的长城,其总长大约是6700000m,将6700000用科学记数法表示为(          
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

3.如图是由5个完全相同的小正方体堆成的物体,其主视图是(  )
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

4.下列计算正确的是(  )
A
3a+4b7ab
Bx12÷x6x6
C.(a+22a2+4
D
.(ab33ab6

5.下列图形中,既是轴对称图形,又是中心对称图形的是(  )
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

6.函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的自变量 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的取值范围在数轴上可表示为(     
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

7.某校举行“遵守交通安全,从我做起”演讲比赛.7位评委给选手甲的评分如下:91958993889495,则这组数据的众数和中位数分别是(  )
A
9592
B
9393
C
9392
D
9593

8.如图,正六边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 内接于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中点,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

9.用计算机处理数据,为了防止数据输入出错,某研究室安排两名程序操作员各输入一遍,比较两人的输入是否一致,本次操作需输入2640个数据,已知甲的输入速度是乙的2倍,结果甲比乙少用2小时输完.这两名操作员每分钟各能输入多少个数据?设乙每分钟能输入x个数据,根据题意得方程正确的是(  )
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

10.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中,点DE为边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的三等分点,点FG在边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,点H <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的交点.若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
A1
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
C
2
D
3

11.对于实数ab定义运算“”为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,例如 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则关于x的方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的根的情况,下列说法正确的是(       
A
.有两个不相等的实数根
B
.有两个相等的实数根
C
.无实数根
D
.无法确定

12.对于正数x,规定 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,例如: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> (  )
A
199
B
200
C
201
D
202

评卷人

得分




二、填空题

13.分解因式:x3﹣xy2=_____

14.ab互为相反数,c8的立方根,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ___________

15.如图,用圆心角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 半径为6的扇形围成一个圆锥的侧面(接缝忽略不计),则这个圆锥的高是______
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

16.出入相补原理是我国古代数学的重要成就之一,最早是由三国时期数学家刘徽创建.“将一个几何图形,任意切成多块小图形,几何图形的总面积保持不变,等于所分割成的小图形的面积之和”是该原理的重要内容之一、如图,在矩形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,对角线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 交于点O,点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 边上的一个动点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,垂足分别为点FG,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

17.已知ab是方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的两根,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的对边分别为abc,且满足 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的值为___________

19.如图,四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是边长为4的正方形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是等边三角形,则阴影部分的面积为___________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

20.如图,在平面直角坐标系中,O为坐标原点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 垂直于x轴,以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 为对称轴作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的轴对称图形,对称轴 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 与线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 相交于点F,点D的对应点B恰好落在反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的图象上,点OE的对应点分别是点CA.若点A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中点,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则k的值为___________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

评卷人

得分




三、解答题

21.计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

22.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中,D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中点,E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中点,过点A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(2)
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,求证:四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是矩形.

23.某校为落实国家“双减”政策,丰富课后服务内容,为学生开设五类社团活动(要求每人必须参加且只参加一类活动):A.音乐社团;B.体育社团;C.美术社团;D.文学社团;E.电脑编程社团,该校为了解学生对这五类社团活动的喜爱情况,随机抽取部分学生进行了调查统计,并根据调查结果,绘制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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
根据图中信息,解答下列问题:
(1)
此次调查一共随机抽取了___________名学生,补全条形统计图(要求在条形图上方注明人数);
(2)
扇形统计图中圆心角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ___________度;
(3)
现从“文学社团”里表现优秀的甲、乙、丙、丁四名同学中随机选取两名参加演讲比赛,请用列表或画树状图的方法求出恰好选中甲和乙两名同学的概率.

24.某中学依山而建,校门A处有一坡角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的斜坡 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,长度为30米,在坡顶B处测得教学楼 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的楼顶C的仰角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,离B4米远的E处有一个花台,在E处测得C的仰角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的延长线交水平线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点D,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的长(结果保留根号).
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    

25.如图,在平面直角坐标系中,一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的图象在第一象限内交于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 两点,直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> x轴相交于点C,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
(1)求一次函数与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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时,请结合函数图象,直接写出关于x的不等式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解集;
(3)
过点B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 平行于x轴,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点D,求梯形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的面积.

26.如图,以线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 为直径作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,交射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点D,过点D作直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的延长线于点E,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的延长线于点F.连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的延长线于点M
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
(1)求证:直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时,判断 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的形状,并说明理由;
(3)
在(2)的条件下, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点P,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的长.

27.某水果种植基地为响应政府号召,大力种植优质水果.某超市看好甲、乙两种优质水果的市场价值,经调查,这两种水果的进价和售价如下表所示:

水果种类

进价(元千克)

售价(元)千克)

a

20

b

23

该超市购进甲种水果15千克和乙种水果5千克需要305元;购进甲种水果20千克和乙种水果10千克需要470元.
(1)
ab的值;
(2)
该超市决定每天购进甲、乙两种水果共100千克进行销售,其中甲种水果的数量不少于30千克,且不大于80千克.实际销售时,若甲种水果超过60千克,则超过部分按每千克降价3元销售.求超市当天售完这两种水果获得的利润y(元)与购进甲种水果的数量x(千克)之间的函数关系式,并写出x的取值范围;
(3)
在(2)的条件下,超市在获得的利润y(元)取得最大值时,决定售出的甲种水果每千克降价 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 元,乙种水果每千克降价m元,若要保证利润率( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> )不低于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,求m的最大值.

28.如图,在平面直角坐标系中,抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> x轴交于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(1)
求该抛物线的函数表达式;
(2)
若点P是直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 下方抛物线上的一动点,过点Px轴的平行线交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点K,过点Py轴的平行线交x轴于点D,求与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的最大值及此时点P的坐标;
(3)
在抛物线的对称轴上是否存在一点M,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 为一条直角边的直角三角形:若存在,请求出点M的坐标,若不存在,请说明理由.

参考答案

1.A

【解析】
根据数轴上某个数与原点的距离叫做这个数的绝对值的定义进行求解即可.
解:在数轴上,点-2到原点的距离是2,所以-2的绝对值是2
故选:A

2.B

【解析】
6700000=6.7×10
6
故选B
点睛:此题主要考查了用科学记数法表示较大的数,一般形式为a×10n

3.A

【解析】
找到从正面看所得到的图形即可,注意所有的看到的棱都应表现在主视图中.
解:从正面看易得左边一列有2个正方形,中间与右边一列各有一个正方形.
故选:A

4.B

【解析】
根据同类项的定义、同底数幂的除法性质、完全平方公式、积的乘方公式进行判断.
解:A3a4b不是同类项,不能合并,所以此选项不正确;
Bx12÷x6x6,所以此选项正确;
C、(a+22a2+4a+4,所以此选项不正确;
D、(ab33a3b9,所以此选项不正确;
故选:B

5.A

【解析】
根据中心对称图形与轴对称图形的概念,进行判断即可.把一个图形绕某一点旋转 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,如果旋转后的图形能够与原来的图形重合,那么这个图形就叫做中心对称图形;如果一个图形沿一条直线折叠,直线两旁的部分能够互相重合,这个图形叫做轴对称图形.
解:A、既是轴对称图形,又是中心对称图形,符合题意;
B
、既不是轴对称图形,也不是中心对称图形,不符合题意;
C
、是轴对称图形,不是中心对称图形,不符合题意;
D
、不是轴对称图形,是中心对称图形,不符合题意,
故选:A

6.D

【解析】
根据二次根式有意义的条件,求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解集,再在数轴上表示即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故在数轴上表示为:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
故选:D

7.D

【解析】
根据众数和中位数的定义求解.
解:这组数据从小到大排序为:88899193949595
95
出现了2次,出现次数最多,所以这组数据的众数为95
这组数据最中间数为93,所以这组数据的中位数是93
故选:D

8.C

【解析】
先计算正六边形的中心角,再利用同圆或等圆中,等弧对的圆心角相等,圆周角定理计算即可.
如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
正六边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选C.

9.D

【解析】
设乙每分钟能输入x个数据,则甲每分钟能输入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 个数据,根据“甲比乙少用2小时输完”列出分式方程即可.
解:设乙每分钟能输入x个数据,则甲每分钟能输入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 个数据,
由题意得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选:D

10.C

【解析】
由三等分点的定义与平行线的性质得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中位线,易证 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 为边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的三等分点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的中位线,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选:C

11.A

【解析】
先根据新定义得到关于x的方程为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,再利用一元二次方程根的判别式求解即可.
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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,
故选A

12.C

【解析】
通过计算 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 可以推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 结果.

解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故选:C

13.xx+y)(x-y

【解析】
先提取公因式x,再对余下的多项式利用平方差公式继续分解.
解:x3-xy2=xx2-y2=xx+y)(x-y),
故答案为:x(x+y)(x-y)

14. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
利用相反数,立方根的性质求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> c的值,代入原式计算即可得到结果.
解:根据题意得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

15. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
由圆心角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,半径为6的扇形求弧长= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可求圆锥底面圆周长: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,如图由圆锥高OD,底面圆半径DC,与母线OC构成直角三角形,由勾股定理 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 即可.
解:圆心角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,半径为6的扇形弧长= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
圆锥底面圆周长: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
如图由圆锥高OD,底面圆半径DC,与母线OC构成直角三角形,
由勾股定理 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
这个圆锥的高是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,根据矩形的性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,根据勾股定理得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,根据三角形的面积公式即可得到结论.

解:连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
利用一元二次方程的解的定义和根与系数的关系,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,从而得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,然后代入,即可求解.
解:∵ab是方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的两根,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,求解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,再利用正弦的定义求解即可.
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

19. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 点,首先求出正方形的面积,然后根据等边三角形和正方形的性质求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,从而求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的面积,最后作差求解即可.
解:如图所示,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是边长为4的正方形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是等边三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,由对称的性质知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,利用相似三角形的判定和性质求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 以及反比例函数的几何意义求解即可.
解:连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
设对称轴 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> x轴交于点G
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 关于对称轴 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

21.4

【解析】
根据有理数乘方、特殊角三角函数值、负整数指数幂、零指数幂结合二次根式的混合运算法则进行计算即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

22.(1)见解析;
(2)
见解析;

【解析】
1)根据两直线平行,内错角相等求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,然后利用“角角边”证明三角形全等,再由全等三角形的性质容易得出结论;
2)先利用一组对边平行且相等的四边形是平行四边形证明四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是平行四边形,再根据一个角是直角的平行四边形是矩形判定即可.
1)证明:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
2)证明: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
平行四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是矩形.

23.(1)200,补全条形统计图见解析
(2)54
(3)
恰好选中甲、乙两名同学的概率为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
1)用B类型社团的人数除以其人数占比即可求出参与调查的总人数;用总人数减去ABDE四个类型社团的人数得到C类型社团的人数,即可补全条形统计图;
2)用 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 乘以C类型社团的人数占比即可求出扇形统计图中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的度数;
3)先画出树状图得到所有等可能性的结果数,再找到恰好选中甲和乙两名同学的结果数,最后依据概率计算公式求解即可.
1)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ()
C类型社团的人数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ()
补全条形统计图如图,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>    
故答案为:200
2)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
故答案为:54
3)解:画树状图如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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,其中恰好选中甲、乙两名同学的结果有2种,
恰好选中甲、乙两名同学的概率为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

24. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,首先根据坡度求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,并通过矩形的判定确定出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,然后通过解三角形求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即可相加得出结论.
解:如图所示,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则由题意,四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 为矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 为矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
由题意, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 为等腰直角三角形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,经检验, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是上述方程的解,且符合题意,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 米.

25.(1)反比例函数为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,一次函数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(3)9

【解析】
1)利用 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 可得反比例函数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,再求解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,再利用待定系数法求解一次函数的解析式即可;
2)由一次函数的图象在反比例函数图象的上方,结合 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 可得答案;
3)求解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,结合过点B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 平行于x轴,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,再利用梯形的面积公式进行计算即可.
1)解:∵反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
反比例函数为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
一次函数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
2)由一次函数的图象在反比例函数图象的上方,结合 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 可得
不等式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解集为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,同理可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
过点B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 平行于x轴,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 于点D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
梯形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的面积为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

26.(1)见解析
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是等边三角形,理由见解析
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

【解析】
1)证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即可证明直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的切线;
2)证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,据此计算即可证明结论成立;
3)利用含30度的直角三角形的性质求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,得到等边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的边长,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 中,利用余弦函数即可求解.
1)证明:连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的半径,
直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的切线;
2)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是等边三角形,理由如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是等边三角形;
3)解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 是等边三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的直径, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>

27.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(3)1.2

【解析】
1)根据题意列出二元一次方程组求解即可;
2)设购进甲种水果的数量的数量为x千克,则购进乙种水果的数量的数量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 千克,根据题意分两种情况: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,然后分别表示出总利润即可;
3)首先根据题意求出y的最大值,然后根据保证利润率( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> )不低于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 列出不等式求解即可.
1)由题意列方程组为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
2)设购进甲种水果的数量的数量为x千克,则购进乙种水果的数量的数量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 千克,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
综上所述, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
3)当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时,y取最大值,此时 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> (元),
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> (元),
由上可得:当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 时,y取最大值520(元),
由题意可得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
m的最大值为1.2

28.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
(2)
存在, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 代入抛物线解析式求解即可;
2)可求直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ),可求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,从而可求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,即可求解;
3)过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 交抛物线的对称轴于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 交抛物线的对称轴于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> , 可求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,可求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,进而求出直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的解析式,即可求解.
1)解:由题意得
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
2)解:设直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则有
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
3)解:存在,
如图,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 交抛物线的对称轴于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 交抛物线的对称轴于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的对称轴为直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,则有
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> ,且经过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>
综上所述:存在, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a> 的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</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/1005/" title="内江" class="c1" target="_blank">内江</a> <a href="/tags/1074/" title="四川省" class="c1" target="_blank">四川省</a> <a href="/tags/1004/" title="四川" class="c1" target="_blank">四川</a>