分解因试(x-1)²-2(x-1)+1 x³y-2x²y²+xy³

问题描述:

分解因试(x-1)²-2(x-1)+1 x³y-2x²y²+xy³

(x-1)²-2(x-1)+1
=[(x-1)-1]²
=(x-2)²
x³y-2x²y²+xy³
=xy(x²-2xy+y²)
=xy(x-y)²