等比数列{a
n}的前n项和为S
n,已知对任意的n∈N
*,点(n,S
n),均在函数y=b
x+r(b>0)且b≠1,b,r均为常数)的图象上.
(1)求r的值;
(2)当b=2时,记b
n=
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100050853850698/SYS201311031000508538506018_ST/0.png)
(n∈N
*),求数列{b
n}的前n项和T
n.
考点分析:
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