简便计算:1+1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/09 04:17:04

简便计算:1+1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90
简便计算:1+1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90

简便计算:1+1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90
1+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+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9+1/9-1/10
=2-1/10
=1.9

1+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+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9+1/9-1/10
=1+1/2+1/2-1/10
=1又9/10

1+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+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9+1/9-1/10
=2-1/10
=1.9
好久没有做这种数学题了