数列an,bn满足anbn=1,an=namp;sup2;+3n+2,则bn的前十项之和是?
<p>问题：数列an,bn满足anbn=1,an=namp;sup2;+3n+2,则bn的前十项之和是?<p>答案：↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">林延平的回答：<div class="content-b">网友采纳 bn=1/an=1/(n^2+3n+2)=1/[(n+1)(n+2)]=1/(n+1)-1/(n+2) S10=b1+b2+...+b10 =1/2-1/3+1/3-1/4+...+1/11-1/12 =1/2-1/12 =5/12
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