计算：[(x+y)(x-y)-(x-y)^2+2y(x-y)]/(-2y)

计算:(x-y)^2*(y-x)^2*(x-y)^6 计算(x+y)(x+y)^2(-x-y)^3 计算:(-x-2y) * (3x-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)+【- 1、x(x-y)(x+y)-x(x+y)^2 [(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y 计算2x/x^2-y^2 3x/y^2-x^2 y/(x y)(y-x)快! 计算【3(x-y)^2(x+y)^-2/4(x+y)^2(x-y)^-2】^-2 计算(x-2y)^2-4(2x+y)(y-2x)+4x(y-2) 计算：(x-y)(x+2y)+(2x-y)(2x+y) 计算（2x-3y)(x+4y)-(3x+y)(x-2y) [(2x+y)(x-3y)+y(x+3y)]÷(2x)计算,