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> 在等差数列{an}中,a3+a8=8,则S10=(  )                           ...

在等差数列{an}中,a3+a8=8,则S10=(  )                           ...

问题详情:

在等差数列{an}中,a3+a8=8,则S10=(  )                                                       

A.20                                B.40                                C.60                                D.80

在等差数列{an}中,a3+a8=8,则S10=(  )                           ...在等差数列{an}中,a3+a8=8,则S10=(  )                           ... 第2张

【回答】

B【分析】由已知利用等差数列的通项公式和前n项和公式求解.                                

【解答】解:∵在等差数列{an}中,a3+a8=8,                                                       

∴S10=在等差数列{an}中,a3+a8=8,则S10=(  )                           ... 第3张在等差数列{an}中,a3+a8=8,则S10=(  )                           ... 第4张=在等差数列{an}中,a3+a8=8,则S10=(  )                           ... 第5张在等差数列{an}中,a3+a8=8,则S10=(  )                           ... 第6张=5×8=40.                                                 

故选:B.                                                                                                          

【点评】本题考查等差数列的前10项和的求法,是基础题,解题时要认真审题,注意等差数列的*质的合理运用.                                                                                       

                                                                                                                       

知识点:数列

题型:选择题

标签: 等差数列 S10 a3a88
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