2 3 / 3 3\ / 2 2\ 2 2 2 \x + y / - \x + y / + 3*x *y *(x + y)
(x^3 + y^3)^2 - (x^2 + y^2)^3 + 3*x^2*y^2*(x + y)^2
1*(x + 0)*(y + 0)
(1*(x + 0))*(y + 0)
(x^3 + y^3)^2 - (x^2 + y^2)^3 + 3.0*x^2*y^2*(x + y)^2
(x^3 + y^3)^2 - (x^2 + y^2)^3 + 3.0*x^2*y^2*(x + y)^2