简算.1/1X2+1/2X3+1/3X4+1/4X5+.+1/199X200,

分类: 作业答案 • 2022-09-25 14:50:16

问题描述：

简算.
1/1X2+1/2X3+1/3X4+1/4X5+.+1/199X200,

答

1/1X2+1/2X3+1/3X4+1/4X5+.+1/199X200
= 1/1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+.+1/199-1/200
=1-1/200
=199/200