已知数列a
n的各项为正数,前n和为S
n,且
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102747346714736/SYS201311031027473467147016_ST/0.png)
.
(1)求证:数列a
n是等差数列;
(2)设
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102747346714736/SYS201311031027473467147016_ST/1.png)
,求T
n.
考点分析:
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}的所有项按照从大到小,左大右小的原则写成如图所示的数表,第k行有2
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在正方体ABCD-A
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1C
1D
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1C
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A.4
B.3
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