1/1x2+1/2x3+1/3x4+...+1/n(n+1)怎么算

分类: 作业答案 • 2021-12-20 01:30:51

问题描述：

答

1/1x2+1/2x3+1/3x4+...+1/n(n+1)
=1-1/2+1/2-1/3+1/3-1/4+.+1/n-1/(n+1)
=1-1/(n+1)
=n/(n+1)