名校
解题方法
1 . 已知离散型随机变量
的分布列为
若
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
X | 0 | 1 |
P |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39d9a8dc1d0be0b09e45bf8eb296a272.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f412feb8dcad5599ddfe1d1ceb00ac0b.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
名校
2 . 已知函数
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1044dcf4fba551e1b7fbfeb895ea08c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfc45f485fd69c910ff1b777fc87bf47.png)
A.1 | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
名校
解题方法
3 . 为了解学生的体能情况,抽取某学校一、二年级部分学生进行跳绳测试,将所得的数据整理后画出频率分布直方图(如图),设一年级跳绳次数为
,二年级跳绳次数为
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13c91db0da2a076c2ed5e074125ac5f0.png)
______
.(填“
”或“
”)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/096b1ece1dcd29c59a46a4b3e02cb548.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5031a3a951c4a1d1c5e9f80a5e26513.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13c91db0da2a076c2ed5e074125ac5f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79c91ae3927b20381ce27d14489fc733.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/392cdb9d30684cce244bef94b8d861b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ff7942da6c3fc4005256fb1458557c0.png)
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名校
解题方法
4 . 设
为等差数列
的前n项和,
,
.
(1)求数列
的通项公式;
(2)求
;
(3)若
,
,
成等比数列,求m的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5170584604571b5e1afd5ece941e2e73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23005bd2386f15812ce36833200d019d.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6899bf9cadae2ccdb14cbc87d4f280ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e985ada7a866d897f0d061aa965af671.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1752474698cd5466dd180df0a00ba9c.png)
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名校
解题方法
5 . 某人射击一次击中目标的概率是
,经过3次射击,此人有2次击中目标的概率为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eac97e6740365c85ad857aff85cefbe5.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
名校
6 . 设函数
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9b75a0e2b34489ba51328d1b30e7ee0.png)
__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b923078510697d5f7f9ea392eb76dd9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9b75a0e2b34489ba51328d1b30e7ee0.png)
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7 . 已知等比数列
中,
,且
,那么
的值是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a27d520a002d3eebd1758e2c05c15c3f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d27182444d3da4003680f07ec299087c.png)
A.15 | B.31 | C.63 | D.64 |
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名校
8 . 设
是等差数列,且
,
,则数列
的前
项和
的最大值是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b13a6e1d671215fc96e4bee3541d1096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41e7f395f753da570e66cfcf3f5df752.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
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名校
9 . 若随机变量X的分布列如下,且
,则随机变量X的方差
等于__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8441349d50ccee714d5d7f796a12f028.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90a0722562d03a0a55a6c63e5d4cc338.png)
X | 0 | 1 | 2 |
P | a | b |
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名校
10 .
和
的等比中项是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f8c4c029e552954bd493b49aeab82d5.png)
您最近一年使用:0次