解题方法
1 . 已知函数
,
.
(1)证明:
.
(2)证明:
.
(3)若
,求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fa6be945eb11c0498223950886460a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d463f5ad0920eaa291f87a5528c53f4.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d0d3e1b8a17cfb8266d19316c37ed8b.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce084a09377c15254a57339698454923.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fa208de679a96467488aa9655ee1f6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/481f86b6e9c3eb6707a665bb55d18646.png)
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2 . 已知公差不为0的等差数列
,前n项和为
,且
,_____.
现有条件:
;
;
.请从这三个条件中任选一个补充在上面题干中,并解决下面问题.
(1)求数列
的通项公式;
(2)若
,求数列{bn}的前n项和
.
(注:如果选择多个条件分别解答,按第一个解答计分.)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
现有条件:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fbd39d2e3eeef71b04ec59f74b091e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf003ccc2fd8aa62b0d6a98d0666771a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a603fd1e721cae04e5c5c2014280edba.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/216876de04325fd250c38c485cbc34b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
(注:如果选择多个条件分别解答,按第一个解答计分.)
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3 . 若数列
是等比数列,且
,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/1e81c85c03636630979bd90a4f6627e5.png)
A.数列![]() |
B.数列![]() |
C.数列![]() |
D.数列![]() |
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4 . 设数列
为正项等比数列,
为公比,
为前
项的积,且
,
,
,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/115da54f93de5e89d1e7f443fccb61f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/183717ba05a0a954db7233f20c04262b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/928cca3d16082f989ed38ba12b6f562f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3dba40b59fa9e90c0ec1034730b2d596.png)
A.![]() |
B.![]() |
C.![]() |
D.![]() ![]() ![]() |
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5 . 刚考入大学的小明准备向银行贷款a元购买一台笔记本电脑,然后上学的时候通过勤工俭学来分期还款.小明与银行约定:每个月月末还一次款,分12次还清所有的欠款,且每个月还款的钱数都相等,贷款的月利率为t.则小明每个月所要还款的钱数为( )元.
A.![]() |
B.![]() |
C.![]() |
D.![]() |
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解题方法
6 . 已知数列
的前
项和
.
(1)求证:
是等差数列;
(2)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/56c60f23e6ab26477288a9c7803070d0.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b91adba8efbf964e9e35547b0fd0ea36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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解题方法
7 . 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).
表一
(1)经分析,可用线性回归模型拟合y与x的关系,请求出线性回归方程,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:
,
,
的方差为200)
(2)基于上述调查,某校提倡学生周末自主学习.经过一学期的实施后,抽样调查了220位学生.按照是否参与周末自主学习以及成绩是否有进步进行统计,得到2×2列联表(表二).依据表中数据,判断是否有99.9%的把握认为“周末自主学习与成绩进步”有关.
表二
附:
,
, ![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bc485c58dbd6e50bfb352030f4a1c42.png)
表一
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 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdf37396d25dd2c541a97515001463ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b833bde4c0057f63a7fafcdf2c7eb395.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97ea8f47d8d8d9e1832d52b1c7425450.png)
(2)基于上述调查,某校提倡学生周末自主学习.经过一学期的实施后,抽样调查了220位学生.按照是否参与周末自主学习以及成绩是否有进步进行统计,得到2×2列联表(表二).依据表中数据,判断是否有99.9%的把握认为“周末自主学习与成绩进步”有关.
表二
没有进步 | 有进步 | 合计 | |
参与周末自主学习 | 35 | 130 | 165 |
末参与周末自主学习 | 25 | 30 | 55 |
合计 | 60 | 160 | 220 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81ec30e9316c79d956b7c9a483a91632.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ebff20f21ae41fd8d1f1e3145895842.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bc485c58dbd6e50bfb352030f4a1c42.png)
![]() | 0.10 | 0.05 | 0.010 | 0.005 | 0.001 |
k | 2.706 | 3.841 | 6.635 | 7.879 | 10.828 |
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8 . 若正项等比数列
的前
项和为
,且
,则
的最小值为( )
![](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/4e80dfbd9dd4815a11bddf2f5893fb19.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b16bac4081e998f87e4b151fdc8e24f0.png)
A.22 | B.24 | C.26 | D.28 |
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9 . 已知等差数列
的公差
,数列
为正项等比数列,且
,
,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/812be9806122241c476ba1db516c4823.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89fe0f4e8a80a2840c0f6929a8a6351b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b71c6e56da5da4a3cc0b2da1cf9dbbe9.png)
A.![]() | B.![]() |
C.若![]() ![]() | D.若![]() ![]() |
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10 . 点P是曲线
上一个动点,则点P到直线
的距离的最小值是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6201963fcdd54887f2af50518bd908a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e23fc11a3a7592c68b20f93bdde2ed3f.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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