meili 发表于 2022-10-27 14:54:05

【1+1/3+1/6+1/10+1/15+1/21+1/28求答案】

<p>问题:【1+1/3+1/6+1/10+1/15+1/21+1/28求答案】
<p>答案:↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">马峻峰的回答:<div class="content-b">网友采纳  1+1/3+1/6+1/10+1/15+1/21+1/28  =1+2*(1/6+1/12+1/20+1/30+1/42+1/56)  =1+2*(1/2*3+1/3*4+1/4*5+1/5*6+1/6*7+1/7*8)  =1+2*(1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8)  =1+2*(1/2-1/8)  =1+2*3/8  =1+3/4=7/4
页: [1]
查看完整版本: 【1+1/3+1/6+1/10+1/15+1/21+1/28求答案】