Question

(a-2)(a+2)(a^2+4)^2-(a^2+1)^2+2(a+1)^2

Answer 1

(a-2)(a+2)(a^2+4)^2-(a^2+1)^2+2(a+1)^2=
=$a^{2}$+2a-2a-4^(2a+4)^2-2a-1^2+2a+2^2
=$a^{2}$-8a-16^2-2a-2+2a+4
=$a^{2}$-8a-32-2+4
=$a^{2}$-8a-30