若1+x与1-y互为倒数,且xy不等于0,则1/x-1/y=
问题描述:
若1+x与1-y互为倒数,且xy不等于0,则1/x-1/y=
答
(1+x)(1-y)=1
1-y+x-xy=1
x-y-xy=0,两边同时除以xy,
1/y-1/x-1=0
1/x-1/y=-1