数列
的前
项和为
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9aa8c8737223748f099a5c437f3a2cb.png)
(1)写出
的值,并求
的通项公式;
(2)正项等差数列
的前
项和为
,且
,并满足
,成等比数列.
(i)求数列
的通项公式
(ii)设
,试确定
与
的大小关系,并给出证明.
![](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/b9aa8c8737223748f099a5c437f3a2cb.png)
(1)写出
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed529240a883f68f0921e818addeb9c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)正项等差数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.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/08b6f02731cfe96d404a446d0b8bccc4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/975a03319e38805eb6e5baa4febe03a4.png)
(i)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(ii)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccf5c50376dddd9144cc896a76b1aab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63f5c583c98a1fd516c6ceaa60b55dec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b2a698891d42c70b597f0da4f215f09.png)
更新时间:2020-02-07 21:42:20
|
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【推荐1】设公差不为0的等差数列
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(2)若
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(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
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(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cfd2ac66b3882ecf957fdb54c795b79.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b6b479fb3859de81052b575f6b4ddd0.png)
您最近一年使用:0次
解答题-证明题
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较难
(0.4)
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【推荐2】如果存在常数
,使得数列
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(1)若数列:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00b50284b0058b20b7ae5e63db2e47e7.png)
是“兑换系数”为
的“兑换数列”,求
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e53f3ed849beaa4b8b2b22baf49055b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(1)若数列:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00b50284b0058b20b7ae5e63db2e47e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12aab2189a2ba339749cdc8b7e96b357.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)已知有穷等差数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d7e9f86738335a22298559db41037a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e5d534dadff2c6feaca4060ea972ff3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d7e9f86738335a22298559db41037a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(3)对于一个不小于3项,且各项皆为正整数的递增数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
您最近一年使用:0次
【推荐1】已知数列中,
,
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(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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较难
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【推荐2】设数列
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您最近一年使用:0次