Question

因式分解:(a+2b)^2 + (a-2b)^2 - 2(a^2 - 4b^2)

Answer 1

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

=(a+2b)^2 + (a-2b)^2 - 2(a+ 2b)(a-2b)

=[a+2b-(a-2b)]^2

=16b^2