试题与答案

设数列{an}的前n项和为Sn,已知a1=1,Sn+1=4an+2(n∈N*).

题型:解答题

题目:

设数列{an}的前n项和为Sn,已知a1=1,Sn+1=4an+2(n∈N*).

(1)设bn=an+1﹣2an,证明数列{bn}是等比数列;

(2)求数列{an}的通项公式.

答案:

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