【已知数列{an}的前n项和为Sn,且满足Sn+n=2an(n∈N*).(1)证明:数列{an+1}为等比数列,并求数列{an}的通项公式;(2)若bn=(2n+1)an+2n+1,数列{bn}的前n项和为Tn.求满足不等式Tn−22n−1>2023】
<p>问题:【已知数列{an}的前n项和为Sn,且满足Sn+n=2an(n∈N*).(1)证明:数列{an+1}为等比数列,并求数列{an}的通项公式;(2)若bn=(2n+1)an+2n+1,数列{bn}的前n项和为Tn.求满足不等式Tn−22n−1>2023】<p>答案:↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">曹晔的回答:<div class="content-b">网友采纳 (1)证明:当n=1时,2a1=a1+1,∴a1=1.∵2an=Sn+n,n∈N*,∴2an-1=Sn-1+n-1,n≥2,两式相减得an=2an-1+1,n≥2,即an+1=2(an-1+1),n≥2,∴数列{an+1}为以2为首项,2为公比的等比数列,∴an+1=2n,∴an=2n-1...
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