名校
解题方法
1 . 为了了解高中学生课后自主学习数学时间(x分钟/每天)和他们的数学成绩(y分)的关系,某实验小组做了调查,得到一些数据(表一).
(1)求数学成绩y与学习时间x的相关系数(精确到0.001);
(2)请用相关系数说明该组数据中y与x之间的关系可用线性回归模型进行拟合,并求出y关于x的回归直线方程,并由此预测每天课后自主学习数学时间为100分钟时的数学成绩(参考数据:
,
)
(3)基于上述调查,某校提倡学生周末在校自主学习.经过一学期的实施后,抽样调查了220位学生.按照是否参与周末在校自主学习以及成绩是否有进步统计,得到2×2列联表(表二).依据表中数据及小概率值α=0.001的独立性检验,分析“周末在校自主学习与成绩进步”是否有关.
附:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e899162845139a714837b6579fe7806d.png)
随机变量![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a11d85b59b9a6fc77c726dbcd2d1941.png)
编号 | 1 | 2 | 3 | 4 | 5 |
学习时间x | 30 | 40 | 50 | 60 | 70 |
数学成绩y | 65 | 78 | 85 | 99 | 108 |
(2)请用相关系数说明该组数据中y与x之间的关系可用线性回归模型进行拟合,并求出y关于x的回归直线方程,并由此预测每天课后自主学习数学时间为100分钟时的数学成绩(参考数据:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79dd7bdbbb6a060cd79550553659e607.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9a3500f94bba6a26b8d5afe2b250c7a.png)
(3)基于上述调查,某校提倡学生周末在校自主学习.经过一学期的实施后,抽样调查了220位学生.按照是否参与周末在校自主学习以及成绩是否有进步统计,得到2×2列联表(表二).依据表中数据及小概率值α=0.001的独立性检验,分析“周末在校自主学习与成绩进步”是否有关.
没有进步 | 有进步 | 合计 | |
参与周末在校自主学习 | 35 | 130 | 165 |
未参与周末不在校自主学习 | 25 | 30 | 55 |
合计 | 60 | 160 | 220 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e899162845139a714837b6579fe7806d.png)
随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a11d85b59b9a6fc77c726dbcd2d1941.png)
![]() | 0.010 | 0.05 | 0.010 | 0.005 | 0.001 |
![]() | 2.706 | 3.841 | 6.635 | 7.879 | 10.828 |
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解题方法
2 . 已知向量
,
.
(1)若
,求
与
夹角的正弦值;
(2)若
,求向量
的坐标.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40c3bef47eca74c23c275cc0ea1839b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/076a5954a138c685a5b2f3ec8205988a.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/150020a962b0ebb1cedee57c48cf9b07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bf21fef3026cfe445a855c94cab5c84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
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3 . 已知
、
、
是任意的非零向量,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a0b19e69be46452425916a0fcb49c9.png)
A.非零向量![]() ![]() ![]() ![]() ![]() ![]() |
B.![]() |
C.若![]() ![]() ![]() |
D.![]() |
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4 . 已知复数
的虚部不为零,同时满足
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2010a2a275043202d038e64f18846df6.png)
A.![]() | B.![]() |
C.![]() | D.![]() ![]() |
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5 . 已知不共线的向量
、
,若向量
与
共线,则实数k的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/384a33a75de170e49f55eb2b38cfa001.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0035fcdc6a2dfb5836f4dc93dcaf9386.png)
A.1 | B.![]() | C.![]() | D.![]() |
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6 . 已知正方体
的棱长为
,
分别是
的中点,则过这三点的截面面积是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b199a99e53d67ff4abf233930961a29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/744096649aef7e210b191091e9f6c51b.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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7 . 已知复数
,
,则
在复平面内对应的点所在的象限为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bc4197a11da7bf73ce579dc40ff0db2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31060d1fc715ddd24db0bd516cea2044.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e4e2b866b0043a32fc78326553841d3.png)
A.第一象限 | B.第二象限 | C.第三象限 | D.第四象限 |
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8 . 如图所示数阵,第
行共有
个数,第m行的第1个数为
,第2个数为
,第
个数为
,规定:
.
(2)从第1行起,每一行最后一个数依次构成数列
,设数列
的前
项和为
,是否存在正整数
,使得对任意正整数
,
恒成立?如存在,请求出
的最大值;如不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ecdd4f87e7e7e32d723d7e97d980db42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0623207595425920f16e76a7f8f268b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a29a285201fd7e0ad70fa7431cb89a79.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df0749c4129afc0c704155f522290b25.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ae0b861522b18be1753acc4474cbc9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5222268dda9dcb9b660f3cbedbb37757.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4f1e3925bda80e8223bf7e431585847.png)
(2)从第1行起,每一行最后一个数依次构成数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.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)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23e8660fb54ba32b037b392b75316087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
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名校
解题方法
9 . 已知数列
是等差数列,其前
和为
,
,
,数列
满足![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b343307c9d1ae2ab87fdcd873782933.png)
(1)求数列
,
的通项公式;
(2)若对数列
,
,在
与
之间插入
个2(
),组成一个新数列
,求数列
的前83项的和
.
![](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/9c9b6e51986fe5d7a7265e0e93adcb4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b2395ccadbeb8353ead0d573ca02c25.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b343307c9d1ae2ab87fdcd873782933.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若对数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f255d0395fba51ca2d44293cca42e0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/217b927efe12a98e1082ecd7f035b921.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/233427826eb2233641fc3a9805f6d206.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cad52924df9291d5d191d18e09374ee1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b783cf91e34e692ce8e171f0965cb53f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b783cf91e34e692ce8e171f0965cb53f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea50a511b4b1adecf65c932327d07031.png)
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名校
解题方法
10 . 已知
是正项数列
的前
项积,且
,将数列
的第1项,第3项,第7项,…,第
项抽出来,按原顺序组成一个新数列
,令
,数列
的前
项和为
,且不等式
对
恒成立,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.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/0b126acb59207c1478f317fd5e188879.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de777c4e44546bcfe26ad5b6bb418052.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5214be4ab4c116b6d8beb768db721cfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df57c4df55b1d63c5bfa330940a351ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.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/380ddfd4e5671a323aae3c7074b233ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71b78297a65e7fad69635b19928ecc10.png)
A.数列![]() |
B.![]() |
C.![]() |
D.实数![]() ![]() |
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