名校
解题方法
1 . 若随机变量
,且
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/873629c61ce0acaad6886ed5d86624dd.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53c1ed67167078ea4f5f1ee53ee14164.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895e67215220c2be8cdaaf77cf5a6186.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/873629c61ce0acaad6886ed5d86624dd.png)
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2 . 如图,在四棱锥
中,正方形
的边长为3,点
,
分别在棱
,
上(不含端点)
,
,且
,点
在棱
上,
.
;
(2)若点
到平面
的距离为2,
,求直线
与平面
所成角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04fb30a9d07e410ac92c34b8ad0133db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4679758f9909846bbd68101338bae273.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c48a0fa3854ffc0d6e04ab4b2f697ccb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0cee0f36dc452e58086832c0152b641.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13508fdc9e840fe612431360a6d451ee.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85aeab3aeaf4367b711da8cde2e8bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
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3 . 无人机在农业领域的应用对提高农业生产效率,促进农业产业的发展有着极为重要的意义.某地统计了该地近5年的农业无人机保有量,其中用了两种记录方式:
根据上表中的数据,可得
关于
的经验回归方程为
,则( )
年份代码 | 1 | 2 | 3 | 4 | 5 |
无人机数量 | 490 | 510 | 550 | 570 | 580 |
无人机数量 | 4.9 | 5.1 | 5.5 | 5.7 | 5.8 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49172e22b8e7a2fd4a39f79639bfb429.png)
A.![]() ![]() ![]() |
B.![]() |
C.预测第6年该地农业无人机的保有量约为612架 |
D.![]() ![]() ![]() |
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解题方法
4 . 为研究男生和女生对数学课程的喜爱程度是否有差异,运用
列联表进行检验,经计算得
,参考下表,则认为“男生和女生对数学课程的喜爱程度有差异”犯错误的概率不超过( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b72fcdc709e77910cd36a26369648b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a249f8e6ea0d8cd5cb0fd97396bffdd9.png)
0.100 | 0.050 | 0.025 | 0.010 | 0.001 | |
2.706 | 3.841 | 5.024 | 6.635 | 10.828 |
A.![]() | B.![]() | C.![]() | D.![]() |
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5 . 已知数列
满足
,
,设
.
(1)求数列
的通项公式;
(2)记
的前
项和为
,若存在
使得
成立,求实数
的取值范围.
![](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/3d73a6a60e1893c63193699e2642c7d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/314501f06c7e4bf3112fe41ecac7be68.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a37a59558292ad6b3d0978bfd7484990.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/213ee7bd6169aea17d0676c42a071a9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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解题方法
6 . 已知离心率为
的椭圆
的左、右焦点分别为
,
,上顶点为
,线段
的中点为
,射线
与
交于点
,若
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/851a5d6ec23256f9b4a9e98aa92945fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/183b6a0cef4256c9696a5bca31053da5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7272356beb98a7953a49651324cb6455.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f31f96cf332eb02e7a1cf084579663f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9055f58bf6bb8d6c55dcc14b2ae51b4c.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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7 . 已知直线
与圆
和圆
都相切,则实数
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72205f560031db36f9887adcc9cf231c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d61985901c2bc698d72ac88f4e1eb65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff3b7c3d7371d4845b39e76e650d1a3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
A.![]() | B.![]() | C.![]() | D.![]() ![]() |
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8 . 已知曲线
的切线中有且只有一条与直线
平行,则该切线的方程为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6505f30569251838d0a8ea691c0aff67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df0f282a3c1349dad913e80b17186bc3.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
9 . 已知直线
经过抛物线
的焦点
,与
交于不同的两点
,与
的准线
交于点
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bdca0e8a3760f472469d30b1f624c26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d939b804513036cd96fddce791ece09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
A.![]() |
B.若![]() ![]() |
C.若![]() ![]() ![]() |
D.若![]() ![]() |
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10 . 设等差数列
的前
项和为
,公差为
,则下列结论正确的是( )
![](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/e523ee9dbd5e1db226e76c81e356bd3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85cd8c916a1dcb733e56b7a15cae1079.png)
A.![]() | B.当![]() ![]() |
C.![]() | D.使得![]() ![]() |
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