计算（2x-3y)(x+4y)-(3x+y)(x-2y)

计算:(-x-2y) * (3x-y) 计算(x+y)(x+y)^2(-x-y)^3 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)+【- 计算【3(x-y)^2(x+y)^-2/4(x+y)^2(x-y)^-2】^-2 (x-3y)(y+2x)-(4y-3x)(3x+4y)计算 计算（2x-3y)(x+4y)-(3x+y)(x-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) 计算:[(2x - 3y)^2 - (x-y)(4x+2y)] / 2y 计算:1/(x-y)-1/(x+y)-2y/(x^2+y^2)-4y^3/(x^4+y^4)-8x^7/(x^8+y^8 计算2x/x^2-y^2 3x/y^2-x^2 y/(x y)(y-x)快! 计算：（3x-4y）-[-（2y+x）+（x-3y）]-6x [(2x+y)(x-3y)+y(x+3y)]÷(2x)计算,