分解因式(急~~~明天要的!!!!!!!)

1.
x²+7x+12=(x+3)(x+4)

2.
(x²-xy)²-(xy-y²)²
=x²(x-y)²-y²(x-y)²
=(x²-y²)(x-y)²
=(x+y)(x-y)³

1...(X+3)(X+4)
2.根据A^2 +B^2 =(A+B)(A-B)的道理
上式变为(x^2-xy+xy-y^2)(x^2-xy-xy+y^2)=(x^2-y^2)(X-Y)^2
=(X-Y)(X+Y)(X-Y)^2=(X+Y)(X-Y)^3

1. x²+7x+12=(x+3)(x+4)

2. (x²-xy)²-(xy-y²)²
=(x²-xy+xy-y²)(x²-xy-xy+y²)
=(x²-y²)(x-y)²
=(x+y)(x-y)³