3x^3-3x^3-y^2+5y+x^2-5y+y^2等于多少

x(x-y)2-(y-x)3 化简:5(x-y)+2(x+y)-3(x-y) 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) [2/3x-2/x+y(x+y/3x-x-y)]/x-y/x 化简：{2/3x-2/(x+y)[(x+y)/3x-x-y]}/(x+y)/x 计算2/3x-2/x+y(x+y/3x-x-y)/x-y/x 化简3x-2/(x+y)[(x+y)/3x-x-y]÷(x-y)/x (2x-3y)-(5x-y) (2X-3y)-(5x-y) (2x-5y)(3x+y) (2x+y)²+(x+3y)(x-3y)-x(5x+8y)因式分解 因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y) [2(x-y)^5-8(x-y)^2(x+y)+6y(x-y)^2]÷2(x-y)^2[2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2]÷2(x-y)^2 [(x+2y)(x-2y)-(2x-y)^2+(3x-y))2x-5y)]/(-x)我急用 [(x+2y)(x-2y)-(2x-y)²+(3x-y(2x-5y)]/(-x)的解答 [(3x+y)(x-y)-(2x+3y)(x-y)]*(x-y) 计算：x+2y/x-y+2x/y-x-3y/x-y 化简:(x-3y)(x+y)-(x-2y)(x+2y)-(x-y)平方