Question

Efectuati:
(x^2+y^2)^2-2(x^2+y)(y^2-x)-x^4-y^4

Answer 1

$x^{4} +2 x^{2} y^{2}+ y^{4} -2 x^{2} y^{2}+2 x^{3} -2 y^{3}+2xy+2 x^{4} +2 y^{4}$