Question

2(a+b)平方+a平方-b平方-6(a-b)平方

Answer 1

解

2(a+b)²+a²-b²-6(a-b)²

=2(a+b)²+(a+b)(a-b)-6(a-b)²

=[2(a+b)-3(a-b)][(a+b)+2(a-b)]

=(5b-a)(3a-b)