((2x)^3(xy)^2) + (2xy)^2(-x)^3 = (8x^3)(x^2y^2)+(4x^2y^2)(-x^3)
= 8x^5y^2-4x^5y^2
= 4x^5y^2
((2x)^3(xy)^2)((2xy)^2(-x)^3 = -32x^10y^4