已知数列
满足
,且
.
(1)求数列
的通项公式.
(2)求数列
的前n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3f14a820093a56661a8b057562ec2be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
更新时间:2021-11-27 16:13:22
|
相似题推荐
解答题-问答题
|
适中
(0.65)
【推荐1】已知数列
的前n项和为
,并且满足
,
.
(1)求数列
的通项公式;
(2)若
,数列
的前n项和为
,求
;
(3)在(2)的条件下,是否存在常数
,使得数列
为等比数列?若存在,试求出
;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5478342a512e8b3f529816d45f60c5c7.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7d3d55a85012933f91c5d8d27d8801d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
(3)在(2)的条件下,是否存在常数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa1edc46d061a61a1f44e0a49649890c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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解答题-问答题
|
适中
(0.65)
名校
【推荐2】等比数列
中,已知
.
(1)求数列
的通项公式;
(2)若
分别为等差数列
的第3项和第5项,求数列
的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eda159a2eefebf8954370f44df0935d9.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8eedd5b5ba81010aa9f45afbe62fa77e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a89d1f32c1605cfdb8e8855051b9f6ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a89d1f32c1605cfdb8e8855051b9f6ec.png)
您最近一年使用:0次
【推荐1】已知数列
满足:
,
.
(1)设
,证明:数列
是等比数列;
(2)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/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f639aa2fde8c717aa78e22e13daab1c4.png)
(1)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f1179414a71459a3cfa134ace94302e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)设数列
![](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/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
【推荐2】已知数列
满足
,
.
(1)求数列
的通项公式;
(2)证明:
.
![](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/f3cfc11343590efb61c88b627f479be9.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b6257827fd179f2f03f23d5a9f75bc0.png)
您最近一年使用:0次
【推荐1】某企业为一个高科技项目注入了启动资金1000万元,已知每年可获利25%,但由于竞争激烈,每年年底需从利润中抽取200万元资金进行科研、技术改造与广告投入,方能保持原有的利润增长率,设经过n年后,该项目的资金为an万元.
(1)求a1、a2;
(2)设
, 证明数列{bn}为等比数列,并求出至少需经过多少年,该项目的资金才可以达到或超过翻两番(即为原来的4倍)的目标(取lg2=0.3 );
(3)若
,求数列
的前n项和Sn.
(1)求a1、a2;
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50ee4bac8bd5424a924e5b72e40dbfd9.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16e38242434ddc582d813876acd4b71b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐2】已知数列
中,
,
.
(1)求证:数列
是等比数列;
(2)求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4c04321265a924254adf8835a941a49.png)
(1)求证:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ab8159d658290b9df2453eef6f275b3.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bff68c252bacf58e99d639aadec9daf.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