已知1/x-1/y=3.则代数式(2x+3xy-2y)/(x-2xy-y)..
问题描述:
已知1/x-1/y=3.则代数式(2x+3xy-2y)/(x-2xy-y)..
答
1/X-1/Y=3
(2x+3xy-2y)/(x-2xy-y)
分子分母同除以xy
=(2/y+3-2/x)/(1/y-2-1/x)
=(-2*3+3)/(-3-2)
=3/5