来自石红生的问题
【已知1/x-1/y=3,求(2x-3xy-2y)/(x-2xy-y)】
已知1/x-1/y=3,求(2x-3xy-2y)/(x-2xy-y)
1回答
2020-01-2913:40
【已知1/x-1/y=3,求(2x-3xy-2y)/(x-2xy-y)】
已知1/x-1/y=3,求(2x-3xy-2y)/(x-2xy-y)
1/x-1/y=3
∴(y-x)/xy=3,即y-x=3xy
∴x-y=-3xy
∴(2x-3xy-2y)/(x-2xy-y)
=[2(x-y)-3xy]/[(x-y)-2xy]
=(-6xy-3xy)/(-3xy-2xy)
=9/5