分解因式: (1)-2m2+8mn-8n2 (2)a2(x-1)+b2(1-x) (3)(m2+n2)2-4m2n2.

问题描述:

分解因式:
(1)-2m2+8mn-8n2           
(2)a2(x-1)+b2(1-x)
(3)(m2+n22-4m2n2

(1)-2m2+8mn-8n2
=-2(m2-4mn+4n2),
=-2(m-2n)2
(2)a2(x-1)+b2(1-x),
=(x-1)(a2-b2),
=(x-1)(a+b)(a-b);
(3)(m2+n22-4m2n2
=(m2+2mn+n2)(m2-2mn+n2),
=(m+n)2(m-n)2