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【327822】2023年湖南省常德市中考数学真题

时间:2025-01-20 20:22:23 作者: 字数:17186字
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绝密·启用前

2023年湖南省常德市中考数学真题

题号

总分

得分





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1.答题前填写好自己的姓名、班级、考号等信息

2.请将答案正确填写在答题卡上



评卷人

得分




一、选择题

1. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的相反数是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

2.下面算法正确的是(     )
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

3.不等式组 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的解集是(     )
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

4.我市“神十五”航天员张陆和他的两位战友已于202364日回到地球家园,“神十六”的三位航天员已在中国空间站开始值守,空间站的主体结构包括天和核心舱、问天实验舱和梦天实验舱,假设“神十六”甲、乙、丙三名航天员从核心舱进入问天实验舱和梦天实验舱开展实验的机会均等,现在要从这三名航天员中选2人各进入一个实验舱开展科学实验,则甲、乙两人同时被选中的概率为(     )
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>        
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

5. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (     )
A
5
B
1
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
0

6.下列命题正确的是(     )
A
.正方形的对角线相等且互相平分
B
.对角互补的四边形是平行四边形
C
.矩形的对角线互相垂直
D
.一组邻边相等的四边形是菱形

7.如图1,在正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中,对角线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 相交于点OEF分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 上的一点,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的度数为(     )
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

8.观察下边的数表(横排为行,竖排为列),按数表中的规律,分数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 若排在第ab列,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的值为(     )
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>         <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>         <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>         <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>         <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>         <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>       <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
……
A
2003
B
2004
C
2022
D
2023

评卷人

得分




二、填空题

9.计算:(a2b3=___

10.分解因式: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> _______

11.要使二次根式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 有意义,则x应满足的条件是__________

12.联合国20221115日宣布,全世界人口已达80亿.将8000000000用科学记数法表示为__________

13.若关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 有两个不相等的实数根,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的取值范围是_________

14.我市体育中考有必考和选考项目,掷实心球是必考项目之一,在一次训练中,张华同学掷实心球10次的成绩依次是(单位:米)7.68.58.68.59.18.58.48.69.273.则张华同学撰实心球成绩的众数是__________

15.如图1,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 上一点,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,过点D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> E,将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> A点顺时针旋转到图2的位置.则图2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的值为__________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    

16.沈括的《梦溪笔谈》是中国古代科技史上的杰作,其中收录了计算圆弧长度的“会圆术”,如图. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是以O为圆心, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为半径的圆弧,C是弦 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 上, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .“会圆术”给出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> l的近似值s计算公式: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> __________.(结果保留一位小数)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

评卷人

得分




三、解答题

17.计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

18.解方程组: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

19.先化简,再求值: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,其中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

20.如图所示,一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 相交于点A和点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
(1)m的值和反比例函数解析式;
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,求x的取值范围.

21.党的二十大报告指出:“我们要全方位夯实粮食安全根基,牢牢守住十八亿亩耕地红线.确保中国人的饭碗牢牢端在自己手中”.为了了解粮食生产情况,某校数学兴趣小组调查了某种粮大户2018年至2022年粮食总产量及2022年粮食分季节占比情况如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
请根据图中信息回答下列问题:
(1)
该种粮大户2022年早稻产量是__________吨;
(2)2018
年至2022年该种粮大户粮食总产量的中位数是__________,平均数是__________
(3)
该粮食大户估计2023年的粮食总产量年增长率与2022年的相同,那么2023年该粮食大户的粮食总产量是多少吨?

22.六一”儿童节将至,张老板计划购买A型玩具和B型玩具进行销售,若用1200元购买A型玩具的数量比用1500元购买B型玩具的数量多20个,且一个B型玩具的进价是一个A型玩具进价的1.5倍.
(1)
A型玩具和B型玩具的进价分别是多少?
(2)
A型玩具的售价为12/个,B型玩具的售价为20/个,张老板购进AB型玩具共75个,要使总利润不低于300元,则A型玩具最多购进多少个?

23.今年“五一”长假期间,小陈、小余同学和家长去沙滩公园游玩,坐在如图的椅子上休息时,小陈感觉很舒服,激发了她对这把椅子的好奇心,就想出个问题考考同学小余,小陈同学先测量,根据测量结果画出了图1的示意图(图2).在图2中,已知四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是平行四边形,座板 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 与地面 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 平行, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是等腰三角形且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,靠背 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,支架 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,扶手的一部分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .这时她问小余同学,你能算出靠背顶端 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 点距地面( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> )的高度是多少吗?请你帮小余同学算出结果(最后结果保留一位小数).(参考数据: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    

24.如图,四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的内接四边形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是直径, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的延长线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
(1)求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的切线;
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的长.

25.如图,二次函数的图象与x轴交于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 两点,与y轴交于点C,顶点为DO为坐标原点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
(1)求二次函数的表达式;
(2)
求四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的面积;
(3)
P是抛物线上的一点,且在第一象限内,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,求P点的坐标.

26.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> E,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
(1)求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2)
在如图1中,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,其它条件不变得到图2,在图2中过点D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> F,设H <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,过点H <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> G,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> M
求证:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

参考答案

1.B

【解析】
根据互为相反数的两个数的符号相反即可解答.
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的相反数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故选 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

2.C

【解析】
根据有理数的加减法则计算即可.
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,故A不符合题意;
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,故B不符合题意;
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,故C符合题意;
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,故D不符合题意;
故选:C

3.C

【解析】
分别求出各不等式的解集,再求出其公共解集即可.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解不等式①,移项,合并同类项得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解不等式②,移项,合并同类项得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故不等式组的解集为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故选:C

4.B

【解析】
用列表法表示出所有等可能得结果,然后利用概率公式求解即可.



(乙,甲)

(丙,甲)

(甲,乙)


(丙,乙)

(甲,丙)

(乙,丙)



有表格可得,一共有6种等可能得结果,其中甲、乙两人同时被选中的结果有2种,
甲、乙两人同时被选中的概率为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故选:B

5.A

【解析】
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 变形后整体代入求值即可.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故选:A

6.A

【解析】
根据正方形、平行四边形、矩形、菱形的各自性质和构成条件进行判断即可.
A
、正方形的对角线相等且互相垂直平分,描述正确;
B
、对角互补的四边形不一定是平行四边形,只是内接于圆,描述错误;
C
、矩形的对角线不一定垂直,但相等,描述错误;
D
、一组邻边相等的平行四边形才构成菱形,描述错误.
故选:A

7.C

【解析】
首先根据正方形的性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,然后结合 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,然后证明出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,最后利用三角形内角和定理求解即可.
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是正方形
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故选:C

8.C

【解析】
观察表中的规律发现,分数的分子是几,则必在第几列;只有第一列的分数,分母与其所在行数一致.
观察表中的规律发现,分数的分子是几,则必在第几列;只有第一列的分数,分母与其所在行数一致,故 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 在第20列,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ;向前递推到第1列时,分数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,故分数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 与分数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 在同一行.即在第2042行,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故选:C

9.a6b3

【解析】
试题根据积的乘方运算法则可得 (a2b3= a6b 3.

10. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
首先提公因式,原式可化为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,再利用公式法进行因式分解可得结果.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

11. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ## <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
根据二次根式有意义的条件求解即可.
根据题意得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

12. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
科学记数法的表示形式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的形式,其中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为整数.确定 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的值时,要看把原数变成 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,小数点移动了多少位, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的绝对值与小数点移动的位数相同.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

13. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
若一元二次方程有两个不相等的实数根,则根的判别式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,建立关于k的不等式,解不等式即可得出答案.
解:∵关于x的方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 有两个不相等的实数根,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

14.8.5

【解析】
由众数的概念即可得到答案.
张华同学掷实心球10次的成绩出现频次最高的是8.5米,共3次,故张华同学掷实心球成绩的众数是8.5
故答案为:8.5

15. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ##0.8

【解析】
首先根据勾股定理得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,然后证明出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,进而得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,然后证明出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,利用相似三角形的性质求解即可.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

16.0.1

【解析】
由已知求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的值,代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 得弧长的近似值,利用弧长公式可求弧长的值,进而即可得解.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C是弦 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 上, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 可得O <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 上, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

17.0

【解析】
首先计算负整数指数幂,特殊角的三角函数,零指数幂和绝对值,然后计算加减.
原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

18. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
方程组利用加减消元法求解即可.
解:将① <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 代入①得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
所以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是原方程组的解.

19. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
先计算括号内的减法运算,再计算除法,得到化简结果,再把字母的值代入计算即可.
解:原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

20.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
1)根据一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的图象与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的图象交于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> B两点可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的值,进而可求反比例函数的表达式;
2)观察函数图象,写出一次函数图象在反比例函数图象上方所对应的自变量的范围即可.
1)将点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
2)由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
所以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的坐标分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
由图形可得:当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

21.(1)9.2
(2)160
吨;172
(3)264.5


【解析】
1)用2022年总量乘以早稻所占的百分比求解即可;
2)根据中位数和平均数的概念求解即可;
3)首先求出年增长率,进而求解即可.
1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (吨)
故答案为:9.2
22018年至2022年该种粮大户粮食总产量从小到大排列如下:
120
150160200230
∴2018
年至2022年该种粮大户粮食总产量的中位数是160吨;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (吨)
∴2018
年至2022年该种粮大户粮食总产量的平均数是172吨;
故答案为:160吨,172吨;
3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (吨)
∴2023
年该粮食大户的粮食总产量是264.5吨.

22.(1)A型,B型玩具的单价分别是10/个,15/
(2)
最多可购进A型玩具25

【解析】
1)设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 型玩具的单价为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> /件.依题意列出分式方程,进行求解;
2)根据题意列出不等式进行求解即可.
1)设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 型玩具的单价为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> /件.
由题意得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
经检验, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是原方程的解
B型玩具的单价为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> /
A型,B型玩具的单价分别是10/个,15/个.
2)设购进A型玩具 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 个.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
最多可购进A型玩具25个.

23. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
方法一:过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的延长线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,由平行四边形的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,进而求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据平行线的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,进而求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据等腰三角形三线合一可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,进而求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,利用 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 求解即可;
方法二:过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的延长线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据等腰三角形三线合一可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,进而求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据平行线的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,进而求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 求解即可.
解:方法一:
过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的延长线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是平行四边形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
由题意知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 靠背顶端 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 点距地面 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 高度为
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
方法二:
如图,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的延长线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
由题意知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 靠背顶端 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 点距地面 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 高度为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

24.(1)证明见解析;
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
1)根据“连半径,证垂直”即可,
2)先由“直径所对的圆周角是直角”,证 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是直角三角形,用勾股定理求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 长,再通过三角形相似即可求解.
1)连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为半径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的切线,
2)∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中,由勾股定理得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

25.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2)30
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
1)用两点式设出二次函数的解析式,然后求得C点的坐标,并将其代入二次函数的解析式,求得a的值,再将a代入解析式中即可.
2)先将二次函数变形为顶点式,求得顶点坐标,然后利用矩形、三角形的面积公式即可求得答案.
3)根据各点的坐标的关系及同角三角函数相等的结论可以求得相关联的函数解析式,最后联立一次函数与二次函数的解析式,求得点P的坐标.
1)∵二次函数的图象与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 轴交于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 两点.
设二次函数的表达式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
二次函数的表达式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
顶点的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的面积 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
3)如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是抛物线上的一点,且在第一象限,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</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/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
由勾股定理得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是等腰直角三角形
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
所以过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的直线的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,或 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
所以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 直线与抛物线的两个交点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
即所求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

26.(1)证明见解析
(2)①
见解析,②见解析

【解析】
1)先证出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的垂直平分线,再由线段垂直平分线的性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,最后由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 证得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
2)①连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,由三角形中位线的性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,从而 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,再由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,可证得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,从而 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,又 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,等量代换即可;
先证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,再由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中位线,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,从而 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中点,由于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中点,故得证 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .
1)证明:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的垂直平分线,
又∵E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
2)证明:①连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 分别是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中位线,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
又∵AH分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中位线,   
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中点,
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1035/" title="常德" class="c1" target="_blank">常德</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .