等差数列
的前
项和为
,那么
值的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ecfb810cef755814084384b294c2771.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/520f907d998b6ca7466948ab5a7ff76c.png)
A.130 | B.65 | C.70 | D.以上都不对 |
9-10高二下·河北·期末 查看更多[5]
(已下线)2010年正定中学高二下学期期末考试数学试题(已下线)2011届广东省深圳高级中学高三上学期期中考试数学文卷(已下线)2011届福建省莆田一中高三第四次月考数学文卷(已下线)2011届福建省莆田一中高三第四次月考数学理卷(已下线)2014-2015学年辽宁省师大附中高二上学期10月模块考试数学试卷
更新时间:2010-12-20 10:44:16
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