Question

分解因式。跪求答案。有过程的

9（a-b）²+12（a²-b²）+4（a+b）²
x²y（x-y）²-2xy（y-x）³
要有过程的。

Answer 1

9（a-b）²+12（a²-b²）+4（a+b）²
=[3(a-b)]²+2*3*2*(a+b)(a-b)+[2(a+b)]²
=[3(a-b)+2(a+b)]²
=(5a-b)²

x²y（x-y）²-2xy（y-x）³
=x²y（x-y）²+2xy（x-y）³
=xy(x-y)²[x-2(x-y)]
=xy(x-y)²(2y-x)