若等差数列{an}的公差d≠0，前n项和为Sn，若∀n∈N*，都有Sn≤S10，则_刷题宝

题干

若等差数列{a_n}的公差d≠0，前n项和为S_n，若∀n∈N^*，都有S_n≤S₁₀，则（）

A：∀n∈N^*，都有a_n＜a_n_﹣₁

B：a₉•a₁₀＞0

C：S₂＞S₁₇

D：S₁₉≥0

上一题下一题 0.0难度选择题更新时间:2017-09-14 06:07:15

答案(点此获取答案解析）

D

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