【等差数列{An},{Bn}的前n项和为Sn与Tn,若Sn/Tn=2n/3n+1,则An/Bn的值是?2n-1/3n-1.】
<p>问题：【等差数列{An},{Bn}的前n项和为Sn与Tn,若Sn/Tn=2n/3n+1,则An/Bn的值是?2n-1/3n-1.】<p>答案：↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">李治源的回答：<div class="content-b">网友采纳 S(2n-1)=(A1+A(2n-1))×(2n-1)/2 =(A1+A1+(2n-2)d)×(2n-1)/2 =(A1+(n-1)d)×(2n-1) =An×(2n-1) 同理 T(2n-1)=Bn×(2n-1) / =S(2n-1)/T(2n-1) =2(2n-1)/ =(4n-2)/(6n-3+1) =(2n-1)/(3n-1) An/Bn=(2n-1)/(3n-1)
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