在等差数列an中a10<0,a11>0且a11>a10，数列an的前n项和为Sn,则在Sn中最小的负数为（）_刷题宝

题干

在等差数列an中a10<0,a11>0且a11>a10，数列an的前n项和为Sn,则在Sn中最小的负数为（）

A： $S_{17}$

B： $S_{18}$

C： $S_{19}$

D： $S_{20}$

上一题下一题 0.0难度选择题更新时间:2015-12-14 06:24:59

答案(点此获取答案解析）

C

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