求解小学数学题1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90+1/110=?

问题描述:

求解小学数学题1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90+1/110=?

1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90+1/110=(1-1/2)+(1/2-1/3)+(1/3-1/4)+...+(1/9-1/10)+(1/10-1/11)=1-1/11=10/11