(1+1/2+1/3+1/4+1/5)×(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)×(1/2+1/3+1/4+1/5)

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/12 08:07:17
(1+1/2+1/3+1/4+1/5)×(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)×(1/2+1/3+1/4+1/5)

(1+1/2+1/3+1/4+1/5)×(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)×(1/2+1/3+1/4+1/5)
(1+1/2+1/3+1/4+1/5)×(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)×(1/2+1/3+1/4+1/5)

(1+1/2+1/3+1/4+1/5)×(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)×(1/2+1/3+1/4+1/5)
设1+1/2+1/3+1/4+1/5=a 1/2+1/3+1/4+1/5=b
(1+1/2+1/3+1/4+1/5)*(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)*(1/2+1/3+1/4+1/5)=a*(b+1/6)-(a+1/6)*b=1/6(a-b)=1/6