【(x+2y)^2－(x－y)(3x+y)－5y^2】÷2x化简带过程

数学(x-y)^5*(y-x)^3*(x-y)^2 [(x+2y)^2 -(x+y)(3x-y)-5y^2]÷2x 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) (3x+y)二次方-3(3x-y)(x+y)-(x-2y)(x+3y)要过程! (2X-3y)-(5x-y) [(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y (5x^3-7x^3y+3x^2y)+2x^3-(－7x^3y+3x^2y+7x^3) 1、x(x-y)(x+y)-x(x+y)^2 化简:(x-3y)(x+y)-(x-2y)(x+2y)-(x-y)平方 【x-3y][x+y]-[x-2y][x +2y]-[x-y [(3x+y)(x-y)-(2x+3y)(x-y)]*(x-y) 有这样一道题:"计算(2*x*x*x-3*x*x*y-2*x*y*y)-(x*x*x-2*x*y*y+y*y*y)+【-