问题:
问题描述:
(2a+1/2b)²*(2a-1/b)²
郭方回答:
(2a+1/2b)²*(2a-1/2b)²
=[(2a+1/2b)(2a-1/2b)]²
=[(2a)²-(1/2b)²]²
=(4a²-1/4b²)²