因式分解: (1)2x(a-b)-(b-a); (2)x(x+4)+3; (3)x2-2x+1-y2.

问题描述:

因式分解:
(1)2x(a-b)-(b-a);
(2)x(x+4)+3;         
(3)x2-2x+1-y2

(1)原式=2 x (a-b)+(a-b)=(a-b)(2 x+1);
(2)原式=x2+4x+3=(x+1)(x+3);
(3)原式=(x-1)2-y2=(x+y-1)(x-y-1).