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设等比数列{an}的前n项和为Sn,已知a2=6,6a1+a3=30,求an­和Sn
问题详情:设等比数列{an}的前n项和为Sn,已知a2=6,6a1+a3=30,求an­和Sn【回答】解:设的公比为q,由题设得                                        …………4分解得       ...
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