Answer:
x^8 - x^8
Step-by-step explanation:
(x^2+ y^2) (x^4 + y^4)(X+y)(x-y)
(x^2+ y^2) (x^4 + y^4) (x^2 - y^2)
(x^2+ y^2) (x^2 - y^2) (x^4 + y^4)
(x^4 - y^4) (x^4 + y^4)
(x^8 - y^8)
