等比数列{an}中,a2=4,a5=32,则{an}的前4项和为( )A.8

等比数列{a_n}中,a₂=4,a₅=32,则{a_n}的前4项和为( )

A.8 B.16 C.30 D.32

答案

解析:a₂=4,a₅=32,数列为等比数列.

q=2,a₁=2,a₌=4,a₃=8,a₄=16.

∴S₄=30,故选C.

答案:C

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等比数列{an}中,a2=4,a5=32,则{an}的前4项和为( )A.8

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