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设,,…,,设,其中n为正整数,则用含n的代数式表示S为( ) A. B. C....
设
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164101254368834/SYS201310221641012543688010_ST/0.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164101254368834/SYS201310221641012543688010_ST/1.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164101254368834/SYS201310221641012543688010_ST/2.png)
…,
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164101254368834/SYS201310221641012543688010_ST/3.png)
,设
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164101254368834/SYS201310221641012543688010_ST/4.png)
,其中n为正整数,则用含n的代数式表示S为( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164101254368834/SYS201310221641012543688010_ST/5.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164101254368834/SYS201310221641012543688010_ST/6.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164101254368834/SYS201310221641012543688010_ST/7.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164101254368834/SYS201310221641012543688010_ST/8.png)
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