问题描述: 1/1*4+1/4*7+1/7*10+1/10*13+1/13*16怎样计算简便计算 1个回答 分类:数学 2014-09-23 问题解答: 我来补答 1/[n*(n+3)]=1/3*[1/n-1/(n+3)]所以:1/1*4+1/4*7+1/7*10+1/10*13+1/13*16=1/3*(1-1/4)+1/3*(1/4-1/7)+1/3*(1/7-1/10)+1/3*(1/10-1/13)+1/3*(1/13-1/16)=1/3*(1-1/4+1/4-1/7+1/7-1/10+1/10-1/13+1/13-1/16)=1/3*(1-1/16)=5/16 展开全文阅读