已知数列
的奇数项是首项为1的等差数列,偶数项是首项为2的等比数列.数列
前n项和为
,且满足
,
.
(1)求数列
的通项公式:
(2)若
,求正整数m的值;
(3)是否存在正整数m,使得
恰好为数列
中的一项?若存在,求出所有满足条件的m值,若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](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/81618762bcc7e58dcc6363f51db58bd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2887b30cf73eb5769ffd05bd52deee02.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd30fd90de98cb4e0e7b2ac606089fb8.png)
(3)是否存在正整数m,使得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25e4fa6c79af9a9222ba4166cf64fe2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
更新时间:2016-12-03 13:07:04
|
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(1)求
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(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
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【推荐2】数列{an}是等差数列,
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(2)若
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ab035be13c6237f9fe9339a8ec5a089.png)
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名校
解题方法
【推荐1】已知各项均为正数的等差数列
与等比数列
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(2)将数列
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,试求数列
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8592b997d19abf462dfa657056dea220.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e344c4b85a73ad4655a64b246f89bf54.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)将数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ed900c88cf1ca707255cd73398f6321.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ed900c88cf1ca707255cd73398f6321.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77e538c13119bfa09ed8a2f15cd6ead3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
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【推荐2】已知数列
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(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)令
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(3)记
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您最近一年使用:0次
解答题-问答题
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较难
(0.4)
【推荐1】设二次函数
,对任意实数
,有
恒成立;数列
满足
.
(1)求函数
的解析式和值域;
(2)试写出一个区间
,使得当
时,数列
在这个区间上是递增数列,
并说明理由;
(3)已知
,是否存在非零整数
,使得对任意
,都有
恒成立,若存在,求之;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21ccc267e57f4ddf3ff7eebddb9506de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76c0bd88ad30e02ee640eab5152d7a31.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cfb19f0c37a72b33083ae9319f11a74.png)
(1)求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
(2)试写出一个区间
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30277e0be448b4955903e81e8795e45d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd7f3da15610918720feb933c72053c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
并说明理由;
(3)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14835bf3f00139ccec0694d0924db795.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8e6c05c27ebf006a73c6ead9ed3e1f2.png)
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较难
(0.4)
解题方法
【推荐2】已知
.
(1)判断
在
上的单调性;
(2)已知正项数列
满足
.
(i)证明:
;
(ii)若
的前
项和为
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.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3e87d4c6641d71a33a10329a51ec8c0.png)
(1)判断
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/870ebc2f7aabb028024894568d749934.png)
(2)已知正项数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94f57164b597f420a363936f1cf57d12.png)
(i)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccc5bd3034d1b2e9288d66453a4ae228.png)
(ii)若
![](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/2cc9cc3e41fc2994c6c7efa487447bf4.png)
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