作业帮1/6+1/12+1/20+1/30+1/42+1/52+1/72
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/24 16:49:10
xK
0 D$%'E EΠ #̇Xw2hPLюKRF6&`b̌w
\諸|,,@
1/6+1/12+1/20+1/30+1/42+1/52+1/72
1/6+1/12+1/20+1/30+1/42+1/52+1/72
1/6+1/12+1/20+1/30+1/42+1/52+1/72
=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9
=1/2-1/9
=7/18