名校
解题方法
1 . 已知正项等差数列
的公差为2,前
项和为
,且
成等比数列.
(1)求数列
的通项公式
;
(2)若
求数列
的前
项和.
![](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)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b91c13eaedd3a65b08e71d33a7a7c7a2.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f05b1997d02b7483b7ece61061faba1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b17a9b9bb8bf6bb9865e37f204da5c5.png)
您最近一年使用:0次
2 . 某高校为了提升学校餐厅的服务水平, 组织4000名师生对学校餐厅满意度进行评分 调查,按照分层抽样方法,抽取200位师生的评分(满分100 分)作为样本,绘制如图所示的 频率分布直方图,并将分数从低到高分为四个等级:
的值,并估计满意度评分的
分位数;
(2)若样本中男性师生比为
,且男教师评分为80分 以上的概率为0.8, 男学生评分为80分以上的概率0.55, 现 从男性师生中随机抽取一人, 其评分为80分以上的概率为多少?
(3)设在样本中,学生、教师的人数分别为
,记所有学生的评 分为
,其平均数为
,方差为
,所有教师的评分为
,其平均数为
,方差为
,总样本的平均数为
,方差为
,若
,试求
的最小值.
满意度评分 |
| |||
满意度等级 | 不满意 | 基本满意 | 满意 | 非常满意 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/267c88e52743f3dedd4e60569cb958fe.png)
(2)若样本中男性师生比为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa9c934d84feba963335cc7edf01610e.png)
(3)设在样本中,学生、教师的人数分别为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb785c57f06f8e0051e49a5f1b43fde1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1402b0375d6babc0b979a368d1fbb54e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfbe7f95b5d89f9409ec24536da9e826.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a63cadbf6b0d54955a3c3d1b7a62b14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35ba484662ddaac29c2c44ed136f79c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb525270c748eddaaecc4a549cca250e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9289410bd35c9d57326b93cc7f4c4767.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d41042207515dd2e8349c805e6aee400.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/671f43c79d612c93a6d160335e86e177.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d954d1e6b433661e694eddc231be784.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
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名校
解题方法
3 . 已知
,
是函数
的零点,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9c1f914da4657eca7865982b130b299.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d75442a901f013aeb5c52a7113ae9b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c487295d441397ea078d433e61087cec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67a91d7fa3be7708a277b8a836c5af89.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
4 . 已知
为坐标原点,曲线
在点
处的切线与曲线
在点
处的切线平行,且两切线间的距离为
,其中
.
(1)求实数
的值;
(2)若点
分别在曲线
上,求
与
之和的最大值;
(3)若点
在曲线
上,点
在曲线
上,四边形
为正方形,其面积为
,证明: ![](https://staticzujuan.xkw.com/quesimg/Upload/formula/634eecef5979fe32878d032e9736bcad.png)
附:ln2 ≈ 0.693.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/325cb5d7a2edc99c9bfcf39e6ffc7c5c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/248b75c2ba3d6f870b1a7255e652b8b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b037b9629c12214eb24d990fc9855852.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/addc3241a83f4b61d46402319b7f1da1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c90e8d5d7fed033f48270b1ff825fcd5.png)
(1)求实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62ff2912fd8d93b6e692936d95b727c5.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f44755c5fee4b90266eac73ad47a128.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32595168b1cc7fd374aeb8d833c1cbb8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/579d861f3f214342af735e6f0a8db139.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d3ea1f0e09c8f73a18a08f14188f264.png)
(3)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ae6f48b9a53c0155a692509cf31f7e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5aa69fd8445d01c98634c2e885b47d5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/634eecef5979fe32878d032e9736bcad.png)
附:ln2 ≈ 0.693.
您最近一年使用:0次
5 . 已知抛物线
的焦点为
,
为坐标原点,倾斜角为
的直线
过点
且与
交于
,
两点,若
的面积为
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64447af8454c613a58b11d9274d3da2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25dd698d57d1cf239eb8752aecaaa4f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adbd3e8cf8325999cde03adf845d3dd0.png)
A.![]() |
B.![]() |
C.以![]() ![]() |
D.![]() ![]() |
您最近一年使用:0次
名校
解题方法
6 . 已知
,对任意的
,不等式
恒成立,则实数
的取值范围为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3be362dec96173f246ff747264007817.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fde64f4d3c38e43fbdee24eadc4b0dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50e097722265f5ea129ff0417520f859.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
解题方法
7 . 在棱长为2的正方体
中,
为
的中点,以
为原点,OB,OD,OO1所在直线分别为
轴、
轴、
轴,建立如何所示空间直角坐标系.若该正方体内一动点
,满足
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22a20b689283cc8b311eddae4c8c4242.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49ea83a384f056dadaacfa349cc84130.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bfcaf2a345411411cf94422703e9269.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e588cb555e36f28c5db66d213ef064d4.png)
A.点![]() ![]() | B.![]() ![]() |
C.![]() | D.三棱锥![]() ![]() |
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8 . 已知
为平面上一个动点,
到定直线
的距离与到定点
距离的比等于
,记动点
的轨迹为曲线
.
(1)求曲线
的方程;
(2)过点
的直线
与曲线
交于
,
两点,在
轴上是否存在点
,使得
为定值?若存在,求出该定值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b384412acba251d87902ab928902f16.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63309dbc3612815f6dbdee23d9a10adc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d5989c84e320b504511f23eeb6e7357.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(1)求曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.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/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59880e470359d8e9faf6ae5ce155cf2a.png)
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9 . 如图所示,多面体
,底面
是正方形,点
为底面的中心,点
为
的中点,侧面
与
是全等的等腰梯形,
,其余棱长均为2.
平面
;
(2)若点
在棱
上,直线
与平面
所成角的正弦值为
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ecc1cb55a57dde481f8dd07ab150676.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b312dab930cbbb9a4bb1a99f044dab73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/613dedf2d90e58591b7ac4a250ac7b5d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab8a2ca644d9d7cdb4784a4fd28d3904.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdba1337ec85fa9722cb4b320a82ae6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3653ada76ba0c8afe9d57c8e7832c6ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f44fc60c0b360e1b0708a249e4ce0643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f541f7ae7c39082d202efd28805c54e.png)
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