3(xy^2-x^2y)-2(xy+xy^2)+3x^2y

(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y) （xy-x^2)乘以(xy)/(x-y) x^2-xy-6y^2+3xy+y+2 计算3xy[2xy-x(y-2)+x-1] 计算：3xy[2xy-x（y-2）+x] （-3x^y+2xy)-( )=4x^+xy x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2 已知x-y=4xy，则2x+3xy-2yx-2xy-y xy(xy+1)+(xy+3)-2(x+y+2分之一）-(x+y-1)的平方 (-3分之1xy)的平方×[xy(2x-y)-2x(xy-y的平方)] 因式分解：(2x-y)(x^2+xy-2y^2) xy(x^2-xy)(-3xy^2) 由已知x+y=-2,xy=3那么2(x+xy)-[(xy-3y)-x]-(-xy)等于多少?