已知数列
前n项和为
,
,
,
,设![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f2f05c09a35346b62d8bdaf95bfaea.png)
(1)是否存在常数k,使数列
为等比数列,若存在,求k值,若不存在,说明理由.
(2)求
的表达式,并证明
.
![](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/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18d8e8f821111de8075e5c3dfb22a5d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3978c147211401cfa8f6f6984d4542a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f2f05c09a35346b62d8bdaf95bfaea.png)
(1)是否存在常数k,使数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a323ef99ce96bef2781553fdc1c724e.png)
更新时间:2024-05-23 15:57:04
|
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【推荐1】数列
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(1)判断数列
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(1)判断数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fa97c7ae99ad7a17417f75ea514afd6.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a1f2554444735b544debcd68f4cb28b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13aababf2d1ee2f7c5336857f0fcb7a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
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【推荐2】已知无穷数列
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(3)若
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5dffb9c81395b0af0ff6218c34659574.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c95b6be4554f03bf496092f1acdfbb89.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e06699d84ba9a594d21ba1585fe1f340.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4393a1d553fd7c8beae61d72679f56b5.png)
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(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4663e5f34de1f155c3320dc51488ec62.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/08eb71ecf8d733b6932f4680874dbbf3.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b13a6e1d671215fc96e4bee3541d1096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7dff298384b52ac8cd9a2fc167e7b7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3982b8d0a6dea50b0c4778bcf196450a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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解答题-证明题
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【推荐1】已知正项数列
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(2)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.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/59dd6c97d2ee3e74ba5730f1cbcc1d43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19233b07a3f1ad1bf685c5fac8515592.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc705d98e673cf2b42750462ba4703df.png)
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解答题-问答题
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【推荐2】已知数列
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e91f5915e62b151b18156b548e97ce34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
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(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3203575dca7e5d3233f8e3b5f0d22669.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed4f301232123cb7732d4dfacbd1fcab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7399fcd570d1de4057f2059759d18cc9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/caa104c781e026ca07a0378a37981a79.png)
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