1/3+1/6+1/12+...+1/9900
问题描述:
1/3+1/6+1/12+...+1/9900
答
1/2+1/6+1/12+...+1/9900
=1/1*2+1/2*3+1/3*4+1/4*5……+1/99*100
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+……+1/99-1/100
中间正负抵消
=1-1/100
=99/100