(a+b)²-8(a²-b²)+16(a-b)²

问题描述:

(a+b)²-8(a²-b²)+16(a-b)²

(a+b)²-8(a²-b²)+16(a-b)²
=(a+b)²-8(a+b)(a-b)+[4(a-b)]²
=[(a+b)-4(a-b)]²
=(a+b-4a+4b)²
=(3a+5b)²