1、-a³b³+a²b²-ab
=-ab(a²b²-ab+1)
2、（2m-n）²-（3m+2n）²
=(2m-n+3m+2n)(2m-n-3m-2n)
=(5m+n)(-m-3n)
=-(5m+n)(m+3n)
4、（x²-2x）²-11（x²-2x）+24
=(x²-2x-3)(x²-2x-8)
=(x-3)(x+1)(x-4)(x+2)
5、a²-3a-ab+3b
=a(a-3)-b(a-3)
=(a-3)(a-b)
3、x²+8xy-33y²
=(x+11y)(x-3y)