1 . 已知数列
的前n项和是
,满足
.[
(1)求数列
的通项
;
(2)设
,求
的前n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8083b11b8099d31218d3c24e2ae9fc24.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16187d6ee048663f05c90efd4a6a45c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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2 . 已知等差数列
的前n项和为
等于
![](https://img.xkw.com/dksih/QBM/2016/5/5/1572618199646208/1572618205429760/STEM/7b9e9643d4b3451d8639b12aaf3c555c.png)
![](https://img.xkw.com/dksih/QBM/2016/5/5/1572618199646208/1572618205429760/STEM/8a145c1d69b646f3b65a79a3ddd23b01.png)
A.-90 | B.-27 | C.-25 | D.0 |
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2016-12-02更新
|
819次组卷
|
3卷引用:2015-2016学年河北省成安县一中高二1月月考文科数学试卷
3 . 已知
为等比数列
的前
项和,且
,则
等于
![](https://img.xkw.com/dksih/QBM/2016/12/27/1619411074736128/1619411074932736/STEM/0597f84e84ae40fdaa21e15c3e0bf02d.png)
![](https://img.xkw.com/dksih/QBM/2016/12/27/1619411074736128/1619411074932736/STEM/8a59f22aa85144ff9b6675104af17834.png)
![](https://img.xkw.com/dksih/QBM/2016/12/27/1619411074736128/1619411074932736/STEM/954b0eb40fce4a068e15094aa3fa2108.png)
![](https://img.xkw.com/dksih/QBM/2016/12/27/1619411074736128/1619411074932736/STEM/7304197a5ec7475b842873bd093c145b.png)
![](https://img.xkw.com/dksih/QBM/2016/12/27/1619411074736128/1619411074932736/STEM/b8d26cdb51e44cf0a613031356afad97.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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12-13高三上·湖北黄冈·阶段练习
4 . 一同学在电脑中打出如下若干个圆:○●○○●○○○●○○○○●○○○○○●…,若依此规律继续下去,得到一系列的圆,则在前2 012个圆中共有●的个数是
A.61 | B.62 | C.63 | D.64 |
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名校
5 . 2021年教育部印发的《进一步加强中小学生体质健康管理工作的通知》中提出,中小学校要保障学生每天校内、校外各1小时体育活动时间,每天统一安排30分钟的大课间体育活动.一学校某体育项目测试有
的人满分,而该校有
的学生每天运动时间超过两个小时,这些人体育项目测试满分率为
.
(1)从该校随机抽取三人,三人中体育项目测试相互独立,求三人中满分人数的分布列和期望;
(2)现从每天运动时间不超过两个小时的学生中任意调查一名学生,求他体育项目测试满分的概率;
(3)体育测试前甲、乙、丙三人传球做热身训练,每次传球,传球者等可能地将球传给另外两个人中的任何一人,第1次由甲将球传出,求第n次传球后球在乙手中的概率.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d0797a4e8f5cb2a7746ce2e4ea4e81f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8ee628efd6b2f7296c106dd5cbae42f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b1065ae0947705c7d16a5a86c78f07e.png)
(1)从该校随机抽取三人,三人中体育项目测试相互独立,求三人中满分人数的分布列和期望;
(2)现从每天运动时间不超过两个小时的学生中任意调查一名学生,求他体育项目测试满分的概率;
(3)体育测试前甲、乙、丙三人传球做热身训练,每次传球,传球者等可能地将球传给另外两个人中的任何一人,第1次由甲将球传出,求第n次传球后球在乙手中的概率.
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2024-06-14更新
|
180次组卷
|
2卷引用:河北省邯郸市部分示范性高中2024届高三下学期三模数学试题
6 . 已知数列-1,
,
,-4成等差数列,-1,b1,b2,b3,-4成等比数列,则
的值为
![](https://img.xkw.com/dksih/QBM/2016/1/21/1572456083283968/1572456089067520/STEM/70af9058ca724840a62088f921de4473.png)
![](https://img.xkw.com/dksih/QBM/2016/1/21/1572456083283968/1572456089067520/STEM/c0e79cbaf5664a738b00f4fc23f2ed15.png)
![](https://img.xkw.com/dksih/QBM/2016/1/21/1572456083283968/1572456089067520/STEM/34ad156d5f3b4be48bbce5c6f1540114.png)
A.![]() | B.-![]() | C.![]() ![]() | D.![]() |
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7 . 已知
为等比数列
的前
项和,且
,则
等于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a43a065980cc42bb10ee34953aa2f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fc11a860719719f43ec5c2179902946.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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2017-02-08更新
|
367次组卷
|
2卷引用:2017届河北磁县一中高三11月月考数学(文)试卷
8 . 设
为等比数列{
}的前n项和,
=0,则
=.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92e42f7949210322487e99080a78434a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24287732b9014ff7017d4f9aa9d43c3a.png)
A.10 | B.-5 | C.9 | D.-8 |
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2016-12-03更新
|
893次组卷
|
2卷引用:2015-2016学年河北省邯郸市魏一中等校高二上学期期中文科数学试卷
11-12高三下·江苏·开学考试
9 . 已知集合
,记和
中所有不同值的个数为
.如当
时,由
,
,
,
,
,得
.对于集合
,若实数
成等差数列,则
= _________ .
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/b75ffb69e15a4790b64d6f2e33262003.png?resizew=136)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/4999bdd65fb142a9a46d15e449b8090e.png?resizew=137)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/3adbd0be35a045f39cdd68fa71af2f19.png?resizew=43)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/1855136f6e624fcfa2dff8b13b36c1ff.png?resizew=84)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/725e98675f1e4c209d84d24f6a7d80f9.png?resizew=56)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/2accaf2f9b5646a1950299c55af288bc.png?resizew=56)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/6c173a967e2e4ff493c20e0aed47fd3a.png?resizew=103)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/b81c1fdad10e4a0ba1cb456c849e69fd.png?resizew=60)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/8f251b3b393742578c26865cd7ffa620.png?resizew=60)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/2acebe40b14e4e639290f2a855e084a3.png?resizew=67)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/135297bb7b844a4c8e645cf1cc0dce05.png?resizew=131)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/979dc03b7730487d9744bbbb7ad59f5c.png?resizew=97)
![](https://img.xkw.com/dksih/QBM/2012/11/8/1571057928437760/1571057933983744/STEM/4c9d5f3411b5475185f37b391a21d898.png?resizew=43)
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10 . 已知等差数列
前n项和为Sn.若m>1, m∈N且![](https://img.xkw.com/dksih/QBM/2016/1/21/1572455941390336/1572455947419648/STEM/52ace5525a024882852b63a87e7f7bed.png?resizew=125)
, 则m等于____________ .
![](https://img.xkw.com/dksih/QBM/2016/1/21/1572455941390336/1572455947419648/STEM/4df9dc9b5eff429b8ef880a874483d2f.png?resizew=29)
![](https://img.xkw.com/dksih/QBM/2016/1/21/1572455941390336/1572455947419648/STEM/52ace5525a024882852b63a87e7f7bed.png?resizew=125)
![](https://img.xkw.com/dksih/QBM/2016/1/21/1572455941390336/1572455947419648/STEM/20d6cbfbabcd46eeba845ecd2246a6d5.png?resizew=65)
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