1/2=1-1/2
1/6=1/2-1/3
1/12=1/3-1/4
……
1/9900=1/99-1/100
所以,
原式=(1-1/2)+(1/2-1/3)+(1/3-1/4)+……+(1/99-1/100)
=1-1/100
=99/100
1/2+1/6+1/12+1/20+1/30+…+1/9900
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+....+1/99-1/100
=1-1/100
=99/100
有谁给讲一下
斯柯达热了热卡萨帝测热JS路脸色差爹来PK拉低被DJ