Practice problem
Expand (a−b)(a+b)3−2ab(a2−b2)(a-b)(a+b)^3-2ab(a^2-b^2)(a−b)(a+b)3−2ab(a2−b2).
a4−b4a^4-b^4a4−b4
a4+b4a^4+b^4a4+b4
(a2−b2)2(a^2 - b^2)^2(a2−b2)2
Type a concept, like “slope” or “photosynthesis”.