因式分解: (1)4x2-16; (2)3m2n-12mn+12n; (3)(a2+ab+b2)2-9a2b2.
问题描述:
因式分解:
(1)4x2-16;
(2)3m2n-12mn+12n;
(3)(a2+ab+b2)2-9a2b2.
答
(1)原式=4(x2-4)
=4(x+2)(x-2);
(2)原式=3n(m2-4m+4)
=3n(m-2)2;
(3)原式=(a2+ab+b2-3ab)(a2+ab+b2+3ab)
=(a2-2ab+b2)(a2+4ab+b2)
=(a-b)2(a2+4ab+b2).