y(3x-3y)²-（2y-2x）²（分解因式,

y(3x-3y)²-（2y-2x）²（分解因式,
y(3x-3y)²-（2y-2x）²（分解因式,

y(3x-3y)²-（2y-2x）²（分解因式,
=9y(x-y)²-4（x-y）²
=(x-y)²(9y-4)

y(3x-3y)²-（2y-2x）²
=y*9（x-y)^2-4(x-y)^2
=（x-y)^2(9y-4)

9(x-y)^2-4(x-y)^2
=(9y-4)X(x-y)^2