题目内容
等比数列前n项和为,则m的值为
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等比数列前n项和为54,前2n项和为60,则前3n项和为( )
A.54 B.64 C. D.
等比数列前n项和为Sn,有人算得S1="8," S2="20," S3="36," S4=65,后来发现有一个数算错了,错误的是( )
A.S1 B.S2 C.S3 D.S4
数列{an}为等比数列,前n项和为Sn=-3(22n-1+b),则b=( )
A.1 B. C.-1 D.