(xy)^3·3x^2·(-4x^2y^3)^2
(-3x^y+2xy)-( )=4x^+xy
先化简,再求值:3xy²(-x²y+2x³y²)-4xy(-xy²)·
(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)
x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2
已知x-y=4xy,则2x+3xy-2yx-2xy-y
(2x²y-3xy²)-3(x²y-2xy²)+2(x²y-4xy
已知x-y=4xy,求x-2xy-y分之2x+3xy-2y的值!
xy=-2,x+y=3,求代数式(4xy+12y)+[7x-(3xy+4y-x)]
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
计算3xy[2xy-x(y-2)+x-1]
计算:3xy[2xy-x(y-2)+x]
若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值