名校
1 . 如图所示,九连环是中国的一种古老的智力游戏,它环环相扣,趣味无穷.它主要由九个圆环及框架组成,每个圆环都连有一个直杆,各直杆在后一个圆环内穿过,九个直杆的另一端用平板或者圆环相对固定,圆环在框架上可以解下或者套上.九连环游戏按某种规则将九个环全部从框架上解下或者全部套上.将第
个圆环解下最少需要移动的次数记为
(
且
),已知
,
,且通过该规则可得
,则解下第5个圆环最少需要移动的次数为( )
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/53e47107-09d9-478d-a825-fbfbaef64c9b.png?resizew=222)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38fcec7af3520884b173b29bda6c657a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6842fb24ab3b2235b66ca392ebcbc0be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/249a976e88133f3b3733f09137cf5c42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af9da4fdfdddc259dcef9fdd4b826b64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e2a636c93bcb2dc6e80f43e48dff3fb.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/53e47107-09d9-478d-a825-fbfbaef64c9b.png?resizew=222)
A.7 | B.16 | C.19 | D.21 |
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2020-01-07更新
|
668次组卷
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5卷引用:云南省昆明市2019-2020学年高三下学期1月月考数学(理)试题
2 . 数列
满足
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d211c5a622d0be3b39931d814f9a683.png)
___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b9cff1a9ceaafab92feca53e701b150.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ea8d0e50065114b05ef2dc1ea1129cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d211c5a622d0be3b39931d814f9a683.png)
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3 . 数列
中,
,
,设其前
项和为
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3369ae2337f8d6a049fd8e5a9f313f87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb334e165679c6cb500c994cffa47147.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/d36243198e5e20c56399e4ad5ac3c519.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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4 . 若数列
满足
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42e4487468ab2823d6dbf7f0ebd2eb38.png)
![](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/ab02ab01dc1ab8c9201dd876286ffd37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42e4487468ab2823d6dbf7f0ebd2eb38.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
2017-11-14更新
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6卷引用:云南省昆明市黄冈实验学校2017-2018学年高一下学期第三次月考数学试题
12-13高一下·福建三明·单元测试
5 . 已知数列
的首项
,且
,则
为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7acd84b63e56a59ae51e1872d00f1b53.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f65fc200f10b97588a0c9896277c9c64.png)
A.7 | B.15 | C.30 | D.31 |
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2016-12-02更新
|
873次组卷
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4卷引用:2013-2014学年云南省昆明滇池中学高一下学期期中数学卷
(已下线)2013-2014学年云南省昆明滇池中学高一下学期期中数学卷(已下线)2012-2013福建三明市泰宁一中高一下学期第一次阶段考试数学试卷2013-2014学年湖北武汉蔡甸区第二中学高一下六科竞赛理科数学试卷2013-2014学年湖北武汉蔡甸区第二中学高一下六科竞赛数学文试卷