1/2<1,1/2-1<0,所以 |1/2-1|=1-1/2
同理
1/3<1/2,|1/3-1/2|=1/2-1/3
……
|1/100-1/99|=1/99-1/100
所以原式=1-1/2+1/2-1/3+1/3-1/4+……+1/99-1/100
中间正负抵消
=1-1/100
=99/100
│1/2-1│+│1/3-1/2│+│1/4-1/3│+…+│1/100-1/99│
=1-(1/2)+(1/2)-(1/3)+(1/3)-(1/4)+…
+(1/99)-(1/100)
=1-(1/100)
=99/100
|1/2-1|=1-1/2
|1/3-1/2|=1/2-1/3
以此类推
原式=1-1/100=99/100
1-1/2+1/2-1/3+1/3-.....+1/99-1/100=1-1/100=99/100
所有的都是绝对值所有题目可以写成1-1/2+1/2-1/3+1/4-1/4+1/5……+1/99-1/100=1-1/100=99/100
│1/2-1│+│1/3-1/2│+│1/4-1/3│+……+│1/100-1/99│
=1-1/2+1/2-1/3+1/3-1/4+........+1/99-1/100
=1-1/100
=99/100