已知Sn为数列{an}的前n项和,且向量
=(-4,n),
=(Sn,n+3)垂直.
(1)求数列{an}的通项公式;
(2)数列
前n项和为Tn,求证:Tn<
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a92e6eba8dab638fd66831cd3a0b6d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/427fa45527d0ce469bfd060bf6f991f3.png)
(1)求数列{an}的通项公式;
(2)数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/899650bfd171a1de53add42861866369.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b2a698891d42c70b597f0da4f215f09.png)
更新时间:2017-06-25 21:23:43
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解答题-问答题
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适中
(0.65)
解题方法
【推荐1】已知
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5da4cd81500bdb43118150dbdb1541e6.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
(2)设数列
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