[(x+2y)^2 -(x+y)(3x-y)-5y^2]÷2x

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) (2X-3y)-(5x-y) [(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y 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)+【- [x(x-y)-y(x-y)+(x+y)(x-y)]÷2x其中x=2012 y=2013 先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y