1 . 已知数列
的前
项和为
,
.
(Ⅰ)证明数列
是等比数列,并求数列
的通项公式;
(Ⅱ)设
,求证:
.
![](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/a9880d6badc633e018673b490abe27b6.png)
(Ⅰ)证明数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1413bc2c9162794f2dde9193684696e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
(Ⅱ)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c139cd8b5c5b9b4e959ee1341270a40b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/722a8ffc69ecd6e10f26fffc938d7dc6.png)
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2 . 已知数列
的前
项和为
,
.
(1)证明数列
是等比数列,并求数列
的通项公式;
(2)
,求证:
.
![](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/699b3a920d4eff8610efc8a448976695.png)
(1)证明数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e2de706dc5f0439b989273a5367f63a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c139cd8b5c5b9b4e959ee1341270a40b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/722a8ffc69ecd6e10f26fffc938d7dc6.png)
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真题
3 . 已知数列{an}和{bn}满足:a1=λ,an+1=
其中λ为实数,n为正整数.
(Ⅰ)对任意实数λ,证明数列{an}不是等比数列;
(Ⅱ)试判断数列{bn}是否为等比数列,并证明你的结论;
(Ⅲ)设0<a<b,Sn为数列{bn}的前n项和.是否存在实数λ,使得对任意正整数n,都有
a<Sn<b?若存在,求λ的取值范围;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d498833f7769243d27c82ba997cb09d.png)
(Ⅰ)对任意实数λ,证明数列{an}不是等比数列;
(Ⅱ)试判断数列{bn}是否为等比数列,并证明你的结论;
(Ⅲ)设0<a<b,Sn为数列{bn}的前n项和.是否存在实数λ,使得对任意正整数n,都有
a<Sn<b?若存在,求λ的取值范围;若不存在,说明理由.
您最近一年使用:0次
2019-01-30更新
|
837次组卷
|
3卷引用:2008年普通高等学校招生全国统一考试理科数学(湖北卷)
4 . 已知数列
的前
项和为
,对任意的正整数
,都有
成立.
(1)求证:存在实数
使得数列
为等比数列;
(2)求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.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/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26ec546f3a065c735c17bed3fc5f181c.png)
(1)求证:存在实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5db9887012a594be3cd42a39555c352b.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2ca2b5c44d63be3ad059ce8255ee677.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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5 . 已知各项均为正数的等差数列
的公差
不等于
,设
、
、
是公比为
的等比数列
的前三项.
(1)若
,
.
①求数列
的前
项和
;
②将数列
与
中相同的项去掉,
中剩下的项依次构成新的数列
,设其前
项和为
,求
的值;
(2)若存在
,
、
使得
、
、
、
成等比数列,求证:
为奇数.
![](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/c95b6be4554f03bf496092f1acdfbb89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f255d0395fba51ca2d44293cca42e0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2aab343f7e994c908f3cd031bb988c4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039e4fe671d61e59b96ee525c9df43e8.png)
①求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aec4bdc2a6d4fc387dc621f0b5a268c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
②将数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2770b35b1518ec8b02ac4efa17d605aa.png)
(2)若存在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4c428c12bd1ab65b447a57547b33302.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/699dfd96d64e59252e384847629c7a75.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f255d0395fba51ca2d44293cca42e0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/681ae1522a36768618f7ddaf74abbb7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
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10-11高一下·湖北宜昌·期中
6 . 本小题满分12分)已知等差数列
的前
项和
,且
.
(1)求
的通项公式;
(2)设
,求证:
是等比数列,并求其前
项和
.
![](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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e431d92c5041fa44373c9df45c7309f.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7e6e2e198904f054456646f4352aa3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b7e7cd571c8cd141cbbfe5d0890bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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2016-12-03更新
|
842次组卷
|
5卷引用:2010-2011学年湖北省长阳一中高一第二学期期中考试理科数学卷
(已下线)2010-2011学年湖北省长阳一中高一第二学期期中考试理科数学卷(已下线)2011-2012学年度广东省中山一中高二期中理科数学试卷2014-2015学年福建省德化一中高一下学期期末质量检查数学试卷甘肃省庆阳二中2017-2018学年高二第一次月考数学试卷新疆自治区北京大学附属中学新疆分校2018-2019学年高一下学期期中考试数学试题
7 . 数列
满足:![](https://img.xkw.com/dksih/QBM/2015/7/20/1572187677540352/1572187683332096/STEM/86d291fce5c74caaac8df31796036287.png)
(1)记
,求证:数列
是等比数列;
(2)求数列
的通项公式.
![](https://img.xkw.com/dksih/QBM/2015/7/20/1572187677540352/1572187683332096/STEM/9debf637fda74e44b92f5a93d0f0d880.png)
![](https://img.xkw.com/dksih/QBM/2015/7/20/1572187677540352/1572187683332096/STEM/86d291fce5c74caaac8df31796036287.png)
(1)记
![](https://img.xkw.com/dksih/QBM/2015/7/20/1572187677540352/1572187683332096/STEM/60eb68c6a2e8413d9b9e2bb53f3c63bf.png)
![](https://img.xkw.com/dksih/QBM/2015/7/20/1572187677540352/1572187683332096/STEM/57fa724f3be244368396219681a12ef0.png)
(2)求数列
![](https://img.xkw.com/dksih/QBM/2015/7/20/1572187677540352/1572187683332096/STEM/9debf637fda74e44b92f5a93d0f0d880.png)
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8 . 已知抛物线
,过原点作斜率为1的直线交抛物线于第一象限内一点
,又过点
作斜率为
的直线交抛物线于点
,再过
作斜率为
的直线交抛物线于点
,
,如此继续.一般地,过点
作斜率为
的直线交抛物线于点
,设点
.
![](https://img.xkw.com/dksih/QBM/2015/3/27/1572046076649472/1572046082793472/STEM/18c1fdb630eb4d54a4d8cc6b1799c8b0.png?resizew=225)
(1)求
的值;
(2)令
,求证:数列
是等比数列;
(3)记
为点列
的极限点,求点
的坐标.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e42102c1c07562853219ca5918803a27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56d266a04f3dc7483eddbc26c5e487db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/797e67927616b141ed7c6b83f8b6f4fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa5e9bd516f6282483b92cfe6074623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6c6af45645ea1b7d1e070113b3260d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c15016fc7de1cd5971b7d38c70071e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb9979465ce76b8582067703b39a0bc6.png)
![](https://img.xkw.com/dksih/QBM/2015/3/27/1572046076649472/1572046082793472/STEM/18c1fdb630eb4d54a4d8cc6b1799c8b0.png?resizew=225)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1f0f64e42afb461988de927bb383238.png)
(2)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36f13b98a2f1d21ce4d7afda473d8ded.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
(3)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8e6f975a05b658af66d6f5c816c8cad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1414d14a6de9917963476e30d4079573.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d65eabfb76a6b1a283cb6dff61890701.png)
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12-13高三上·福建龙岩·阶段练习
9 . 成等差数列的三个正数的和等于15,并且这三个数分别加上2,5,13后成为等比数列
中的
,
,
.
(I) 求数列
的通项公式;
(II) 数列
的前n项和为
,求证:数列
是等比数列.
![](https://img.xkw.com/dksih/QBM/2012/2/17/1570751042691072/1570751048081408/STEM/816aa18e09114c84a14bba3cf28558b4.png)
![](https://img.xkw.com/dksih/QBM/2012/2/17/1570751042691072/1570751048081408/STEM/8a0341848bd4470b83f68e8e2e29741a.png)
![](https://img.xkw.com/dksih/QBM/2012/2/17/1570751042691072/1570751048081408/STEM/2565cad12fcd45bbb46832c7aa7221b2.png)
![](https://img.xkw.com/dksih/QBM/2012/2/17/1570751042691072/1570751048081408/STEM/b1885ca46a8e4c53a8bc7c99faef344d.png)
(I) 求数列
![](https://img.xkw.com/dksih/QBM/2012/2/17/1570751042691072/1570751048081408/STEM/816aa18e09114c84a14bba3cf28558b4.png)
(II) 数列
![](https://img.xkw.com/dksih/QBM/2012/2/17/1570751042691072/1570751048081408/STEM/816aa18e09114c84a14bba3cf28558b4.png)
![](https://img.xkw.com/dksih/QBM/2012/2/17/1570751042691072/1570751048081408/STEM/a2b52a0e2a2846d3ac28beff6440a776.png)
![](https://img.xkw.com/dksih/QBM/2012/2/17/1570751042691072/1570751048081408/STEM/e94384c3f78249aa9fbd4cdd176a4e1e.png)
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