求方程x^3y-xy^3+2x^2+2y^2+4=0的解我的卷子上写的是用恒等变形的方法.

方程x^3+y^2-xy^3=2确定y是x的函数y=(x)、求y' 求方程(x+y)/(x^2-xy+y^2)=3/7的整数解1 化简分式方程:x*x-xy-y*y/x*x-3x-6y+2xy 若1/x-1/y=2,求3x-2xy-3y/x-xy-y的值3x-2xy-3y/x-xy-y 不好意思，是3x-2xy-3y/x-2xy-y 当x-y=2xy时,求4x-3xy-4y/xy 已知xy=-2,x-y=3,求（x+y)（x-y)-y^2+（x-y)^2-（6x^2y-2xy^2)÷2y 已知X+Y=3XY,求2X+2Y-XY除以X+Y+2XY的值,要算理.已知X+Y=3XY,求2X+2Y-XY除以X+Y+2XY的值,要算理. 因式分解:12xy^2(y-x)+xy^3(x-y)+4x^2y(x-y) 已知y=3xy+x,求代数式2x+3xy-2y/x-2xy-y的值 若(y-x)/xy=3,求分式(2x+3xy-2y)/(x-2xy-y)的值 若y-x/xy=3,求分式2x+3xy-2y/x-2xy-y 已知x-y/xy=3,求分式2x+3xy-2y/x-2xy-y的值. 已知3/(x-y)=1/xy 求(-x-2xy+y)/ (2x+3xy-2y) 已知x-y=3xy,求2x+3xy-2y/x-2xy-y 已知x-y=3xy,求2x-3xy-2y/x-2xy-y 已知y=3xy+x,求代数式2x+3xy-2y/x-2xy-y的值 x-y+3xy=0 求2x+3xy-2y/x-2xy-y的值 已知X+Y分之XY等于3,求-X+3XY-Y分之2X-3XY+2Y