1 . 设正三角形
的面积为
,作
的内切圆,再作内切圆的内接正三角形
,面积为
,如此下去一系列的正三角形
其面积相应为
设
则
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5518f853e3a929edf3dd3cee8ec0760d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e097c8d4c948de063796bd19f85b3a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5518f853e3a929edf3dd3cee8ec0760d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8321b4034b3ab70b6cbfa25bca18df2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e0bd63f55069a3bc870915010b39225.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25586c3180bb8c1f5fe6e16cee2ee1dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e34155aea2e41d4b9cc517009e4d775.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/114ee2fd926d4dab29c7104c02767525.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba7a750fccecd238519e634de82edbef.png)
A.![]() | B.![]() | C.![]() | D.2 |
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2 . 已知 m 为实数 ,数列
的前 n项和为
,满足
,且
对任何的正整数 n恒成 立.证 明:当 m取 到最大值时,对任何正整数 n都有
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6f18f2c2ec67b5e59e4b3d28795d125.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc93d2c50e5230447ba352cba6e10a59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c03abf00fba72a74cbf971df9a41681.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/deca7f6b51e5c74f60a440b97705cf8e.png)
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2011高三·四川·竞赛
名校
3 . 记实数等 比数列
的前 n项和 为
若
,
,则
=_______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c9b5080aa2e9c889aac8e378d83dfee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f0a561ce4c06bedf2189a84ef09ba55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c689c49954b7fb7305eb92fcbabdbe1.png)
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2018-12-16更新
|
115次组卷
|
3卷引用:2011年全国高中数学联赛四川赛区预赛试题
(已下线)2011年全国高中数学联赛四川赛区预赛试题上海市上海外国语大学附属上外高中2019-2020学年高二上学期期中数学试题沪教版(上海) 高三年级 新高考辅导与训练 第四章 数列与数学归纳法 二、数列的其他问题
4 . 设
,用
表示
的所有非空真子集中各元素之和,
表示
的子集的个数,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/679b3f0be6314a180e92e13bb1147392.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63f5c583c98a1fd516c6ceaa60b55dec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7aac1442ed3d15f31982699d25d8fd45.png)
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2004高三·四川·竞赛
5 . 已知数列
满足
求通项
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5081ca5b4f27e927dbb5f4686ff48339.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9408e3483a9e54c6598e4ce7fb9211f.png)
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6 . 在数列
中,
,其前
项和
满足关系式
(
).
(1)求证:数列
是等比数列;
(2)设数列
的公比为
,作数列
,使
(
),求
.
(3)求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.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/480c365820a675435b5fc66284868565.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7890769dab7cc862d638144bc584c262.png)
(1)求证:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2709ca478fb15ea08e8aa55328eae8e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4a156f7b93cc187b48663a6cc758c17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3948be904275d925cbaae6f2dbc8ab2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/686ece75006ad358f23314dc8a246e11.png)
(3)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e69567f3a83855a706aff0b02f4e9e5.png)
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2018-12-15更新
|
128次组卷
|
6卷引用:【全国百强校】四川省南充高级中学2017-2018学年高一下学期期中考试数学试题
【全国百强校】四川省南充高级中学2017-2018学年高一下学期期中考试数学试题(已下线)2012届江西省师大附中高三10月月考理科数学(已下线)2013届湖南省浏阳一中高三暑假自主学习检测理科数学试卷2016-2017学年河北省武邑中学高一下学期期中考试数学试题卷(已下线)2004年全国高中数学联赛山东赛区预赛试题上海市上海外国语大学附中2016-2017学年高二上学期期中数学试题
7 . 已知函数
,数列
满足
,
.记
.
(1)证明:
为等比数列,并求数列
的通项公式;
(2)记
,求数列
的前
项和公式
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6e9683ea94d06644b7c6e3e3ccbd15f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0736457346c11dd6f458418a4f747ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22c28def0d419a201a4a52c11f150a29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35420c933a18d11fc49362edb04b1be8.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/435c8bd362f1ec652b5969230cac2812.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/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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8 . 设
是小于100的正整数,且满足
为整数.则符合条件的所有正整数
的和为________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ed0acdfe46d62878a3ede562548ae26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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9 . 已知
为正整数数列,
.求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29518f13a1ebc3fff8181c2d7cfba22f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fde5fd4054af57eb71f1933ad80ecef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e811319298c688d1264a792699a5d35.png)
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