(x-2y+4)(x-2y-4) 计算

计算:2xy/(x+y)².(x+y)/4y 计算（2x-3y)(x+4y)-(3x+y)(x-2y)（2x-3y)(x+4y)-(3x+y)(x-2y) (x-3y)(y+2x)-(4y-3x)(3x+4y)计算 计算:(x-y)^2*(x+y)^3*(-x-y)^3*(y-x)^4 计算：[（x+y）³-2(x+y)²-4(x+y)]÷（x+y) 计算[(x+y)的立方-2(x+y)的平方-4(x+y)]÷(-x-y) [(x+2y)(x-2y)+4(x-y)^2-6x]/(6x)计算 计算 (x^8+y^8)(x^4+y^4)(x^2+y^2)(x+y)(x-y) 分式计算(x-y-4y^2/x-y)(x+y-4x^2/x+y)=? 计算:(4xy(x-y)^-1+(x(y^-1)-(x^-1)y)/((x^-1)+(y^-1)))*(x+y)^-2 计算:[(2x - 3y)^2 - (x-y)(4x+2y)] / 2y 计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x^2+xy+y^2) 如何计算4x*4y-2x*2y (x-2y+4)(x-2y-4) 计算 计算(4x^2-y^2)/(2x+y)= 计算：(2x+ )( -y)=4x^2-y^2 计算(3x+y-2)(4x-y+2) 计算 (2X-4Y)(2Y+X)