1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90=多少
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/04/29 09:32:58
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90=多少
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90
=1-1/2+1/2-1/3+1/3-1/4.-1/9-1/10
=1-1/10
=9/10
=1-1/2+1/2-1/3+1/3-1/4.-1/9-1/10
=1-1/10
=9/10