已知数列{an}中,a1=1,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4af77475b912dcdcd55b5bf3c4397cf.png)
(1)证明:数列{an﹣2}为等比数列;
(2)求数列{an}的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4af77475b912dcdcd55b5bf3c4397cf.png)
(1)证明:数列{an﹣2}为等比数列;
(2)求数列{an}的通项公式.
更新时间:2021-09-09 23:36:04
|
相似题推荐
【推荐1】已知
为数列
的前
项和,
.
(1)证明:数列
为等比数列;
(2)求数列
的前
项和
.
![](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/4922a6bf159673b8ade7f3ba04b9aedf.png)
(1)证明:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad801eb3687b2a97af6b218f818a3836.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0496f142d8ae5acb06e83526eaa3ef87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
解答题-问答题
|
较易
(0.85)
【推荐2】已知数列
为等差数列,
,前
项和为
,数列
为等比数列,
,公比为2,且
,
.
(1)求数列
与
的通项公式;
(2)设数列
满足
,求数列
的前
项和
.
![](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/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e396d8c9cf82bc3baa7607cb10cd8f6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad738310491c4720984d59f4db4ad245.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e54931c80d5433647b62120ac1c5a8a.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](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/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
【推荐1】已知数列
,
的通项公式分别为
,
,又
.
(I) 求证数列
是等比数列;
(II) 求数列
的前
项和为
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/606e55241a2e145d54849129b8ffd20f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039271f3111b0e21bc1282fcc22cf016.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e4b5779873cb3f4366dbfdb983dec81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b933d363f5b85a6b4110c9ef030c56a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac07953530e3c248b3438fb200fb1661.png)
(I) 求证数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c84bc401cb7e5a4b0bc1157e5dbd194.png)
(II) 求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c84bc401cb7e5a4b0bc1157e5dbd194.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6f18f2c2ec67b5e59e4b3d28795d125.png)
您最近一年使用:0次
解答题-问答题
|
较易
(0.85)
解题方法
【推荐2】已知数列
满足:
,若
.
(1)求证:数列
是等比数列;
(2)若数列
的前
项和为
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e15e34fe59ee9258b2457671fd8d207d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14a89e23cbb54c644241cd0231c09bbd.png)
(1)求证:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若数列
![](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/3b9a0d7150fb24be3e28ef7f0e18be93.png)
您最近一年使用:0次