1/2+1/6+1/12+1/20+1/30+1/42=
来源：学生作业帮助网 编辑：六六作业网 时间：2024/11/28 13:49:29
1/2+1/6+1/12+1/20+1/30+1/42=1/2+1/6+1/12+1/20+1/30+1/42=1/2+1/6+1/12+1/20+1/30+1/42=1/2+1/6+1/12+1/2
1/2+1/6+1/12+1/20+1/30+1/42=
1/2+1/6+1/12+1/20+1/30+1/42=
1/2+1/6+1/12+1/20+1/30+1/42=
1/2+1/6+1/12+1/20+1/30+1/42
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7
=1-1/7
=6/7
我是老师 谢谢采纳
1/2+1/6+1/12+1/20+1/30+1/42
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7
=1-1/7
=6/7
=1/1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7
=1/1-1/7
=6/7
1/1x1/2+1/2x1/3+1/3x1/4+省略号+1/6x1/7=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7=6/7
6/7