设数列{a
n}的前n和为S
n,已知
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182848321678014/SYS201310241828483216780026_ST/0.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182848321678014/SYS201310241828483216780026_ST/1.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182848321678014/SYS201310241828483216780026_ST/2.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182848321678014/SYS201310241828483216780026_ST/3.png)
,一般地,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182848321678014/SYS201310241828483216780026_ST/4.png)
(n∈N*).
(1)求a
4;
(2)求a
2n;
(3)求和:a
1a
2+a
3a
4+a
5a
6+…+a
2n-1a
2n.
考点分析:
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(理)已知数列{a
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182848321678014/SYS201310241828483216780021_ST/0.png)
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182848321678014/SYS201310241828483216780021_ST/1.png)
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A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182848321678014/SYS201310241828483216780021_ST/2.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182848321678014/SYS201310241828483216780021_ST/3.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182848321678014/SYS201310241828483216780021_ST/4.png)
(n∈N*)
D.以上结论都不对
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