化简：3x^2-[5xy-(x^y-3xy)+4x^2y-8xy]

x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2 （-3x^y+2xy)-( )=4x^+xy 5xy^2-[3xy^2-(4xy^2-2x^y)]+x^2y-xy^2如何化简 -3(xy-2x²)-[y²-(5xy-4x²)+2xy] x+y=8,xy=-2,求(5xy+4x+7y)+(6x-3xy)-(4xy-3y)的值 (x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y) 已知x-y=4xy，则2x+3xy-2yx-2xy-y 化简4xy-3y²-3x²+xy-3xy-2x²+x²-2y² 5x^2y/-1/2xy*3xy^2 [-(x-y)^2/xy]^-4*(y^2-xy/x)^3*(x^4/y^10)÷(xy-y^2/x)^-5=-y(y- 化简!1、（x^2-xy）+xy+y^2 2、3（x^2-xy）-xy+y^2 2x平方y-2xy+3xy平方+5+2xy+x平方y-3xy平方-3 过程!