因式分解: (1)m2n-5mn+6n; (2)a2-b2-2a+1.

问题描述:

因式分解:
(1)m2n-5mn+6n;                    
(2)a2-b2-2a+1.

(1)m2n-5mn+6n
=n(m2-5m+6)
=n(m-2)(m-3);
                    
(2)a2-b2-2a+1
=a2-2a+1-b2
=(a-1)2-b2
=(a-1+b)(a-1-b).