已知数列
的前
项和为
且
,
.
(1)求证
为等比数列,并求出数列
的通项公式;
(2)设数列
的前
项和为
,是否存在正整数
,对任意
,不等式
恒成立?若存在,求出
的最小值,若不存在,请说明理由.
![](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/8d7a9511c3d1b6d41d17df1559919880.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e8adbe4d237aa33ca4d24901df8cfcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
(1)求证
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02b93708dc68d1509f7030bdf7918bae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad83668ff336589f82a2cd04db9f9947.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b04c7ba0ffd54e60b2829f4440c91ec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ae1d8b82b6b00c861167fa7c3a796c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
更新时间:2017-10-09 20:29:12
|
相似题推荐
【推荐1】设数列
的前
项和为
,且满足![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dbbbbd7005d91fe5d18afba668837ab.png)
.
(1)求
;
(2)数列
的通项公式;
(3)设
,求证:
.
![](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)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92b5124c1981cc2b7c4850613d6d3b5d.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
(2)数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb72b465181887a8d5f22b1f7e4c421f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/733c393eb55f776b8383277cc946e200.png)
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解答题-问答题
|
较难
(0.4)
名校
解题方法
【推荐2】已知数列
的首项
,且
,
.
(
)证明数列
是等比数列并求数列
的通项公式.
(
)证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b28ef6f1b2279af482557a8ea46f2e43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/853eace02560e7f1490694276c29a856.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48aac05ba23217b211cfb265543af298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76ad4897a05a6a26b10e2d8379137fa1.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/414656636a840bbb9a031d6103239fdd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebf1dd038a36c7dfed064ef8d389871f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b28ef6f1b2279af482557a8ea46f2e43.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9880952857950577055578875ab29141.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ba52f89159b5c2eea55eb25c0973a28.png)
您最近一年使用:0次
【推荐2】已知函数
对任意实数
都有
,
.
(1)若
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(2)若
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时,
恒成立,求
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1c8ca569e742d9eeee3b85f61bd8e17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b0fffbec1fe851795dfdd448bf0d165.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d87cd4403487962c38c8707ba3ab3fa3.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1c8ca569e742d9eeee3b85f61bd8e17.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f8101a8f0dfea30e5e05aa87c6abdcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0622aacc5deff1bebb000395af718f11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
解题方法
【推荐1】已知各项均为正数的数列
满足:
,设
.
(1)求数列
的通项公式;
(2)求证:
;
(3)若数列
满足
(
为非零常数),确定
的取值范围,使
时,都有
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7377c5386639beb8ad6ca73a8c0d94b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/470583f9ca3ab10ee9a306399ba20966.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f63b998f4909841e47575281936b3f55.png)
(3)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75a9fa7719845f72b055805121f53d2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e145b6046bc80d0ffecc61ac67c87ca1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c74164bcbb550600a8fe2946e5d9844.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
解题方法
【推荐2】已知数列
满足
.
(1)求数列
的通项;
(2)设
,若
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53c811b8b0124c799580b5fa9cae3929.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/980d51ba3340a31964fbec9e6f243ca6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adcbc64b0f3d08d5285ee32e5ca13d73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e6afc5de00034c4b65e5c2841c1e299.png)
您最近一年使用:0次