$\displaystyle (x^2-y^3)^2+(x^2+y^3)(x^2-y^3)+(-2xy^2)(-xy)=$
$\displaystyle = x^4 -2x^2y^3+y^6+x^4-y^6+2x^2y^3=$
$\displaystyle = 2x^4$
- Mer. Giu 26th, 2024
$\displaystyle (x^2-y^3)^2+(x^2+y^3)(x^2-y^3)+(-2xy^2)(-xy)=$
$\displaystyle = x^4 -2x^2y^3+y^6+x^4-y^6+2x^2y^3=$
$\displaystyle = 2x^4$