Question:
\[ (a+b)(a-b)(a^2-ab+b^2)(a^2+ab+b^2) \] is equal to
(a) \[ a^6+b^6 \]
(b) \[ a^6-b^6 \]
(c) \[ a^3-b^3 \]
(d) \[ a^3+b^3 \]
Solution:
\[ =(a^2-b^2)(a^2-ab+b^2)(a^2+ab+b^2) \]
\[ =(a^2-b^2)(a^4+a^2b^2+b^4) \]
\[ =a^6-b^6 \]
\[ \boxed{a^6-b^6} \]