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【327662】2022年广西贺州市中考数学真题

时间:2025-01-20 19:56:36 作者: 字数:16842字
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2022年广西贺州市中考数学真题

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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.下列各数中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的相反数是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
0
C
1
D
2

2.如图,直线ab被直线c所截,下列各组角是同位角的是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

3.在一个不透明的盒子中,装有质地、大小一样的白色乒乓球2个,黄色乒乓球3个,随机摸出一个球,摸到黄色乒乓球的概率是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

4.下面四个几何体中,主视图为矩形的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

5.2022年我国高考报名人数再创新高,约为1193万(即11930000)人,数据11930000用科学记数法表示为(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

6.如图,在RtABC中,∠C=90°,∠B=56°,则∠A的度数为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

7.下列运算正确的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

8.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的值是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

9.已知一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的图象如图所示,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的图象为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

10.如图,在等腰直角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 中,点EOA上,以点O为圆心、OE为半径作圆弧交OB于点F,连接EF,已知阴影部分面积为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,则EF的长度为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
2
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

11.已知二次函数y=2x24x10≤xa时,y取得的最大值为15,则a的值为(       
A
1
B
2
C
3
D
4

12.某餐厅为了追求时间效率,推出一种液体“沙漏”免单方案(即点单完成后,开始倒转“沙漏”, “沙漏”漏完前,客人所点的菜需全部上桌,否则该桌免费用餐).“沙漏”是由一个圆锥体和一个圆柱体相通连接而成.某次计时前如图(1)所示,已知圆锥体底面半径是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,高是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ;圆柱体底面半径是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,液体高是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> .计时结束后如图(2)所示,求此时“沙漏”中液体的高度为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

评卷人

得分




二、填空题

13.若代数式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 在实数范围内有意义,则实数x的取值范围是______

14.因式分解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> __________

15.如图,在平面直角坐标系中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 为等腰三角形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,点Bx轴的距离为4,若将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 绕点O逆时针旋转 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,则点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的坐标为__________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

16.若实数mn满足 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> __________

17.一枚质地均匀的骰子,六个面分别标有数字123456.连续抛掷骰子两次,第一次正面朝上的数字作为十位数,第二次正面朝上的数字作为个位数,则这个两位数能被3整除的概率为__________

18.如图,在矩形ABCD中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> EF分别是ADAB的中点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的平分线交AB于点G,点P是线段DG上的一个动点,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的周长最小值为__________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

评卷人

得分




三、解答题

19.计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

20.解方程: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

21.为了落实“双减”政策,提倡课内高效学习,课外时间归还学生,“鸿志”班为了激发学生学习热情,提高学习成绩,采用分组学习方案,每7人分为一小组,经过半个学期的学习,在模拟测试中,某小组7人的成绩分别为989492889598100(单位:分).
(1)
该小组学生成绩的中位数是__________,众数是__________
(2)
若成绩95分(含95分)以上评为优秀,求该小组成员成绩的平均分和优秀率(百分率保留整数).

22.如图,在小明家附近有一座废旧的烟囱,为了乡村振兴,美化环境,政府计划把这片区域改造为公园.现决定用爆破的方式拆除该烟囱,为确定安全范围,需测量烟囱的高度AB,因为不能直接到达烟囱底部B处,测量人员用高为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的测角器在与烟囱底部B成一直线的CD两处地面上,分别测得烟囱顶部A的仰角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,同时量得CD <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> .问烟囱AB的高度为多少米?(精确到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,参考数据: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

23.如图,在平行四边形ABCD中,点EF分别在ADBC上,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,连接AFCEACEF,且ACEF相交于点O
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
(1)
求证:四边形AFCE是平行四边形;
(2)
AC平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,求四边形AFCE的面积.

24.2022年在中国举办的冬奥会和残奥会令世界瞩目,冬奥会和残奥会的吉祥物冰墩墩和雪容融家喻户晓,成为热销产品,某商家以每套34元的价格购进一批冰墩墩和雪容融套件,若该产品每套的售价是48元时,每天可售出200套;若每套售价提高2元,则每天少卖4套.
(1)
设冰墩墩和雪容融套件每套售价定为x元时,求该商品销售量yx之间的函数关系式;
(2)
求每套售价定为多少元时,每天销售套件所获利润W最大,最大利润是多少元?

25.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 内接于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> AB是直径,延长AB到点E,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,连接EC,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,点D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 上的点,连接ADCD,且CDAB于点F
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
(1)
求证:EC <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的切线;
(2)
BC平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,求AD的长.

26.如图,抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,与y轴交于点C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
(1)
求抛物线的解析式;
(2)
P为抛物线对称轴上一动点,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 是以BC为底边的等腰三角形时,求点P的坐标;
(3)
在(2)条件下,是否存在点M为抛物线第一象限上的点,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ?若存在,求出点M的横坐标;若不存在,请说明理由.

参考答案

1.C

【解析】
根据相反数的定义(只有符号不同的两个数互为相反数)判断即可.
解:由相反数的定义可得:-11互为相反数,
故选:C

2.B

【解析】
两条线ab被第三条直线c所截,在截线的同旁,被截两直线的同一方,把这种位置关系的角称为同位角,据此作答即可.
解:∠1与∠2是对顶角,选项A不符合题意;
∠1
与∠3是同位角,选项B符合题意;
∠2
与∠3是内错角,选项C不符合题意;
∠3
与∠4是邻补角,选项D不符合题意;
故选:B

3.D

【解析】
直接利用概率公式计算即可.
解:因为盒子里由黄色乒乓球3个,
所以随机摸出一个球,摸到黄色乒乓球的情况有3种,
因为盒子里一共有2+3=5(个)球,
一共有5种情况,
随机摸出一个球,摸到黄色乒乓球的概率为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
故选:D

4.A

【解析】
依次分析每个选项中的主视图,找出符合题意的选项即可.
解:A选项图形的主视图为矩形,符合题意;
B
选项图形的主视图为三角形,中间由一条实线,不符合题意;
C
选项图形的主视图为三角形,不符合题意;
D
选项图形的主视图为梯形,不符合题意;
故选:A

5.C

【解析】
首先思考科学记数法表示数的形式,再确定an的值,即可得出答案.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
故选:C

6.A

【解析】
根据直角三角形的两个锐角互余,即可得出∠A的度数.
解:∵RtABC中,∠C=90°,∠B=56°
∴∠
A=90°-∠B=90°-56°=34°
故选:A

7.D

【解析】
利用合并同类项,同底数幂相除,积的乘方,同底数幂相乘法则,逐项判断即可求解.
解:A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,故本选项错误,不符合题意;
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,故本选项错误,不符合题意;
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,故本选项错误,不符合题意;
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,故本选项正确,符合题意;
故选:D

8.B

【解析】
根据相似三角形的判定定理得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,根据相似三角形的面积比等于相似比的平方计算,得到答案.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
故选:B

9.A

【解析】
根据题意可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,从而得到一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的图象经过第一、二、四象限,反比函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的图象位于第一、三象限内,即可求解.
解:根据题意得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的图象经过第一、二、四象限,反比函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的图象位于第一、三象限内.
故选:A

10.C

【解析】
根据题意可得:OE=OF,∠O=90°,设OE=OF=x,利用阴影部分面积列出等式,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,然后由勾股定理求解即可.
解:根据题意可得:OE=OF,∠O=90°
OE=OF=x
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
故选:C

11.D

【解析】
先找到二次函数的对称轴和顶点坐标,求出y=15时,x的值,再根据二次函数的性质得出答案.
解:∵二次函数y=2x2-4x-1=2x-12-3
抛物线的对称轴为x=1,顶点(1-3),
∵1
0,开口向上,
在对称轴x=1的右侧,yx的增大而增大,
0≤xa时,即在对称轴右侧,y取得最大值为15
x=a时,y=15
∴2
a-12-3=15
解得:a=4a=-2(舍去),
a的值为4
故选:D

12.B

【解析】
由圆锥的圆锥体底面半径是6cm,高是6cm,可得CD=DE,根据园锥、圆柱体积公式可得液体的体积为63πcm3,圆锥的体积为72πcm3,设此时“沙漏”中液体的高度AD=xcm,则DE=CD=6-xcm,根据题意,列出方程,即可求解.
解:如图,作圆锥的高AC,在BC上取点E,过点EDEAC于点D,则AB=6cmAC=6cm
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
∴△
ABC为等腰直角三角形,
DEAB
∴△
CDE∽△CAB
∴△
CDE为等腰直角三角形,
CD=DE
圆柱体内液体的体积为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
圆锥的体积为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
设此时“沙漏”中液体的高度AD=xcm,则DE=CD=6-xcm
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
解得:x=3
即此时“沙漏”中液体的高度3cm
故选:B

13. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

【解析】
根据二次根式有意义的条件即可求得数x的取值范围.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 在实数范围内有意义,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

14. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

【解析】
首先提取公因数3,进而利用平方差公式进行分解即可.
解:原式=3(x24)=3(x+2)(x2)
故答案为:3(x+2)(x2)

15. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

【解析】
B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 轴于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,构建 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,即可得出答案.
B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 轴于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
由旋转可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

16.7

【解析】
根据非负数的性质可求出mn的值,进而代入数值可求解.
解:由题意知,mn满足 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
m-n-5=02m+n4=0
m=3n=-2
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
故答案为:7

17. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

【解析】
列出所有可能出现的情况,再得到能被3整除的情况,最后根据概率公式解答.
解:画树状图如下,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
所有等可能的情况共36种,其中组成的两位数中能被3整除的有12152124333642455154636612种,
即这个两位数能被3整除的概率为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

18. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ## <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

【解析】
CD上取点H,使DH=DE,连接EHPH,过点FFKCD于点K,可得DG垂直平分EH,从而得到当点FPH三点共线时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的周长最小,最小值为FH+EF,再分别求出EFFH,即可求解.
解:如图,在CD上取点H,使DH=DE,连接EHPH,过点FFKCD于点K
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
在矩形ABCD中,∠A=∠ADC=90°AD=BC=6CD=AB=8
∴△
DEH为等腰直角三角形,
DG平分∠ADC
DG垂直平分EH
PE=PH
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的周长等于PE+PF+EF=PH+PF+EFFH+EF
当点FPH三点共线时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的周长最小,最小值为FH+EF
EF分别是ADAB的中点,
AE=DE=DH=3AF=4
EF=5
FKCD
∴∠
DKF=∠A=∠ADC=90°
四边形ADKF为矩形,
DK=AF=4FK=AD=6
HK=1
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
FH+EF= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的周长最小为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

19.5

【解析】
根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 解答.
解:原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

20.原方程无解

【解析】
方程两边同时乘以最简公分母 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,先去分母,化为整式方程,再去括号、移项、合并同类项、化系数为1,最后验根即可.
解:方程两边同时乘以最简公分母 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,得
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
解方程,得
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
检验:当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 不是原方程的根,原方程无解.

21.(1)9598
(2)
平均分为95分,优秀率为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

【解析】
1)直接根据中位数与众数的定义求解即可;
2)根据平均数公式求平均数,然后确定优秀的人数所占的比例,再化为百分数即可得到优秀率的值.
(1)
将数据从小到大排列为889294959898100
由于最中间的数是95,出现次数最多的数是98
所以中位数是95,众数是98
(2)
该小组成员成绩的平均分为
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> (分)
95
分(含95分)以上人数为4人,所以优秀率为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
答:该小组成员成绩的平均分为95分,优秀率为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

22.53.2

【解析】
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,得方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,解出x,即求出AB的长.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
解方程,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
答:烟囱AB的高度为53.2

23.(1)详见解析;
(2)24


【解析】
1)根据一组对边平行且相等的四边形是平行四边形解答;
2)由平行线的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,再根据角平分线的性质解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,继而证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,由此证明平行四边形AFCE是菱形,根据菱形的性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,结合正切函数的定义解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,最后根据三角形面积公式解答.
(1)
证明: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 四边形ABCD是平行四边形
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 四边形AFCE是平行四边形.
(2)
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,由(1)知四边形AFCE是平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 平行四边形AFCE是菱形.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

24.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
(2)
每套售价为91元时,每天销售套件所获利润最大,最大利润是6498元.

【解析】
1)根据 “该产品每套的售价是48元时,每天可售出200套;若每套售价提高2元,则每天少卖4套.”列出函数关系式,即可求解;
2)根据利润等于每件的利润乘以销售量,可得到函数关系式,再利用二次函数的性质,即可求解.
(1)
解:根据题意,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> x之间的函数关系式是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
(2)
解:根据题意,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
抛物线开口向下,W有最大值
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
答:每套售价为91元时,每天销售套件所获利润最大,最大利润是6498元.

25.(1)详见解析;
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

【解析】
1)连接OC,证明∠OCE=90°即可;
2)先证明出CDAB,再利用直角三角形的性质和三角函数分别求出∠CADCF后即可求出AD的值.
(1)
证明:连接OC
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的半径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的切线.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
(2)
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> .
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> AB <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

26.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
(2)
P坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
(3)
存在, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>

【解析】
1)把 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 即可的得出抛物线解析式;
2)依题意可得出即P点在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 的平分线上且在抛物线的对称轴上利用等腰三角形的性质,即可得出P点的坐标;
2)利用铅垂线ME,即可表达出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,再由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 即可列出方程求解.
(1)
根据题意,得
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 抛物线解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
(2)
由(1)得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,且点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 是以BC为底边的等腰三角形
PC=PB
OP=OP
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
设抛物线的对称轴与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 轴交于H点,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
抛物线对称轴 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> P坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
(3)
存在.
理由如下:过点M <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 轴,交BC于点E,交x轴于点F
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
设直线BC的解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> ,依题意,得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 直线BC的解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a> E的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
M在第一象限内,且在BC的上方,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1014/" title="广西" class="c1" target="_blank">广西</a> <a href="/tags/1019/" title="贺州" class="c1" target="_blank">贺州</a>