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设等比数列{an}的公比q=2,前n项和为Sn,则=( ) A.2 B.4 C....
设等比数列{a
n}的公比q=2,前n项和为S
n,则
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231000447913910/SYS201311012310004479139004_ST/0.png)
=( )
A.2
B.4
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231000447913910/SYS201311012310004479139004_ST/1.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231000447913910/SYS201311012310004479139004_ST/2.png)
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231000447780374/SYS201311012310004477803021_ST/1.png)
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