计算;/1/3-1/4/+/1/4-1/5/+... ... +/1/19-1/20/

来源:学生作业帮助网 编辑:六六作业网 时间:2025/01/12 05:45:35
计算;/1/3-1/4/+/1/4-1/5/+......+/1/19-1/20/计算;/1/3-1/4/+/1/4-1/5/+......+/1/19-1/20/计算;/1/3-1/4/+/1/4-

计算;/1/3-1/4/+/1/4-1/5/+... ... +/1/19-1/20/
计算;/1/3-1/4/+/1/4-1/5/+... ... +/1/19-1/20/

计算;/1/3-1/4/+/1/4-1/5/+... ... +/1/19-1/20/
/1/3-1/4/+/1/4-1/5/+......+/1/19-1/20/
=1/3-1/4+1/4-1/5+..+1/19-1/20
=1/3-1/20
=17/60

原式=1/3-(1/4-1/4)-(1/5-1/5)-。。。。。-(1/19-1/19)-1/20
=1/3-1/20
=17/60