题目是否有误
应该求 分式x-2xy-y分之2x+3xy-2y的值吧
∵ 1/x - 1/y=3
y-x/xy=3
x-y=-3xy
2x+3xy-2y/x-2xy-y
=2(x-y)+3xy/(x-y)-2xy
=2×(-3xy)+3xy/-3xy-2xy
=-3xy/-5xy
=3/5