名校
1 . 已知等比数列
的前
项和为
,
,
,且
.
(1)求
的通项公式;
(2)是否存在正整数
,使得
成立?若存在,求出
的最小值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.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/039e4fe671d61e59b96ee525c9df43e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2387b578f0a767112fd0d799d9bc90c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef05a461e1e5a8d8d70cf094885736ab.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
(2)是否存在正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e3eca6f129f3ef5b7010698e02280bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
您最近一年使用:0次
名校
2 . 已知无穷等比数列
满足:对任意的
,
,则数列
公比
的取值集合为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8125d21d7a28df27df4fdca76be0b2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
您最近一年使用:0次
2019-09-23更新
|
331次组卷
|
3卷引用:上海市复旦大学附属中学2018-2019学年高一下学期期末考试数学试题
名校
3 . 已知数列
是等比数列,公比为
,且
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad0d99fef1aa4dbcc6dc7b30b7d2c9a9.png)
_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f5e4fd61ce18c07c2262d49824f3d6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc0195871fcbc76a42428e8a7f75a70c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad0d99fef1aa4dbcc6dc7b30b7d2c9a9.png)
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4 . 已知数列
的通项公式为
,
是其前
项和,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bca8f26c7e2cf5c7c4eaf39b089ae52.png)
_____ .(结果用数字作答)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1705c273d0c3edc7666cead63658b4c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bca8f26c7e2cf5c7c4eaf39b089ae52.png)
您最近一年使用:0次
名校
5 . 已知数列
满足
,
,
,则数列
的通项公式为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6065aaa8f3f103d1bc960da8318ce35.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a340088634d6d4820e048916bdd75d96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
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2019-08-21更新
|
667次组卷
|
3卷引用:上海市控江中学2018-2019学年高一下学期期末数学试题
名校
6 . 已知函数
,
是公差为
的等差数列,
是公比为
的等比数列.且
,
,
,
.
(1)分别求数列
、
的通项公式;
(2)已知数列
满足:
,求数列
的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35f47ce72c592e5dab3590d6d0475096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afb43e4bb60398984fbd81c81996247e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/598d8f4c88dd92840aeb912af249d524.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0910b6fd7a8d766a95867b825957ed86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2836c728580184bb0730a53bae3cf99.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38f8ea46f612bb59351eafe3ddaab62f.png)
(1)分别求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)已知数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce849c32e4e7ab938ecd2862b0d55144.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
您最近一年使用:0次
7 . 已知常数
且
,在数列
中,首项
,
是其前
项和,且
,
.
(1)设
,
,证明数列
是等比数列,并求出
的通项公式;
(2)设
,
,证明数列
是等差数列,并求出
的通项公式;
(3)若当且仅当
时,数列
取到最小值,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bd9736828195f010db4e1f0a9dea7a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21ce38c382d325f98f68d357ce72c268.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63c6e0c2d16cda7e8b2b8c588adeb8ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47769ca08edfa79fc200b9f37d197335.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17de11bec49c0896a6a7bc757ab308b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
(1)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ac8e1d60f036093acd1e8fb476226b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/633191ed66bdfa87e2e8fa5f23bf3892.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
(3)若当且仅当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764eff906937f9b1fb58e5abfb2eb8a3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/846fa57d92d6ad44d6a0cafad1e71ed4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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2019-08-21更新
|
917次组卷
|
2卷引用:上海市控江中学2018-2019学年高一下学期期末数学试题
名校
8 . 无穷等比数列
的前
项和为
,若
,且
,则无穷等比数列
的各项和为________ .
![](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/039e4fe671d61e59b96ee525c9df43e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3266da39a9388158ccecd6ed506b461.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
您最近一年使用:0次
2019-12-08更新
|
256次组卷
|
2卷引用:2018年上海市复旦附中高三5月三模数学试题
名校
9 . 已知
是数列
的前
项和,对任意
,都有
;
(1)若
,求证:数列
是等差数列,并求此时数列
的通项公式;
(2)若
,求证:数列
是等比数列,并求此时数列
的通项公式;
(3)设
,若
,求实数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.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/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4faa5d8f3b8d5f59910ef3e885abe4fc.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/711b21672fd907c5c92fee1d649e7003.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46db680bc60929939e0f09990c03583e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ac5c639aa5cd63ab86b2b0d9a23c998.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6788d3dbbd2d5f865db8d414375339e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8ba3d72887756e8d222e0e3ae6aff5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75330ac9e51cdef4bc61012551e1d00b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
您最近一年使用:0次
2019-12-08更新
|
766次组卷
|
3卷引用:2018年上海市复旦附中高三5月三模数学试题
名校
解题方法
10 . 已知数列{an}的前n项和为Sn,且Sn=n﹣5an﹣85,n∈N*
(1)证明:{an﹣1}是等比数列;
(2)求数列{Sn}的通项公式.请指出n为何值时,Sn取得最小值,并说明理由?(参考数据
15=﹣14.85)
(1)证明:{an﹣1}是等比数列;
(2)求数列{Sn}的通项公式.请指出n为何值时,Sn取得最小值,并说明理由?(参考数据
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/605371611ded460283ea3722c4b486d0.png)
您最近一年使用:0次
2019-11-10更新
|
288次组卷
|
3卷引用:上海市复旦附中2018-2019学年高二上学期10月月考数学试题