4xy^2-4x^2y-y^3

x^2y+4xy+4y x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2 （-3x^y+2xy)-( )=4x^+xy 已知x-y=4xy，则2x+3xy-2yx-2xy-y [-(x-y)^2/xy]^-4*(y^2-xy/x)^3*(x^4/y^10)÷(xy-y^2/x)^-5=-y(y- (2x²y-3xy²)-3(x²y-2xy²)+2（x²y-4xy&# xy=-2,x+y=3,求代数式（4xy+12y)+[7x-(3xy+4y-x)] 已知x-y=4xy,求x-2xy-y分之2x+3xy-2y的值! 3x²y+xy²-[2xy²-4x²y+（x²y-2xy²） 若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)} x^+2xy+y^+4=16 x^-2xy+y^=16 求(3xy+6y^)+|x^-(2xy+2y^-3x^)|的值