Question

Calculati (a-b)(a+b)(a^2+b^2)(a^4-b^4)= ?

Answer 1

$(a-b)(a+b)(a^2+b^2)(a^4-b^4)=(a^2-b^2)(a^2+b^2)(a^4-b^4)= \\ =(a^4-b^4)(a^4-b^4)=a^8-a^4b^4-a^4b^4+b^8=a^8-2a^4b^4+b^8$