等比数列{
}的前n 项和为
,已知
,
,
成等差数列.
(1)求{
}的公比q;
(2)若
-
=3,求
.
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/90971a5d37434800a94e9df6804fecdf.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/c24e0a48c49748ad8d0394ec24801d85.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/4bd4555132994faeafcbb15a814ebcb2.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/1f612af06a4544ce92bee1abb72eacf3.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/3dee0026ca324e50bfaf3bbd722b619b.png)
(1)求{
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/90971a5d37434800a94e9df6804fecdf.png)
(2)若
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/0f8fac1e49f74953a4f0c38b7dd61bdb.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/625e092473be4466906224793272d7c4.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/8c771f9805d64444ba7c6746d5a810b8.png)
10-11高一下·黑龙江鹤岗·期中 查看更多[4]
(已下线)2010-2011年黑龙江省鹤岗一中高一下学期期中考试文科数学(已下线)2011-2012学年福建省师大附中高二上学期期末考试理科数学(已下线)2012届山东省潍坊市高二寒假作业(四)数学试卷(已下线)2011-2012学年贵州省遵义四中度高一下学期期期中数学试卷
更新时间:2016-11-30 20:49:13
|
【知识点】 分组(并项)法求和
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解答题-证明题
|
较易
(0.85)
名校
解题方法
【推荐1】已知数列
的前
项和
满足
,等差数列
满足
.
(1)求数列
的通项公式;
(2)设
,求证:数列
的前
项和
.
![](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/c3ddd6d99ad32dd7fdb1797d8cf94786.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56850936cd108a11f2dfa3da9a5880e4.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed48c3e5c53eba20c2e262b7d2c09bfc.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d44ddab6e0c60119be69985ae7fa65b.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/2bdf45fa184303a6991f1197d7493312.png)
您最近一年使用:0次
【推荐2】已知等差数列
的前n项和为
,数列
是等比数列,
,
,
,
.
(1)求数列
和
的通项公式;
(2)若
,设数列
的前n项和为
,求
![](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/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b13a6e1d671215fc96e4bee3541d1096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59dd6c97d2ee3e74ba5730f1cbcc1d43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7306abf622a316800e4c5cae9190a7a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cd59c522b56d8a8519ec6c330707e01.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a7b7507f9e99db51400dc2e9ef00e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9b647ac8a8174071a4f332a00b5507b.png)
您最近一年使用:0次