因式分解: (1)x2y-4y; (2)x2-4y2+x+2y.

问题描述:

因式分解:
(1)x2y-4y;
(2)x2-4y2+x+2y.

(1)x2y-4y
=y(x2-4)
=y(x-2)(x+2);
(2)x2-4y2+x+2y
=(x+2y)(x-2y)+x+2y
=(x+2y)(x-2y+1).