因式分解 (1)6mn2-4m3n (2)4a2-16 (3)a4-2a2b2+b4 (4)(x2+9)2-36x2.
问题描述:
因式分解
(1)6mn2-4m3n
(2)4a2-16
(3)a4-2a2b2+b4
(4)(x2+9)2-36x2.
答
(1)6mn2-4m3n=2mn(3n-2m2);
(2)4a2-16,
=4(a2-4),
=4(a+2)(a-2);
(3)a4-2a2b2+b4,
=(a2-b2)2,
=(a+b)2(a-b)2;
(4)(x2+9)2-36x2,
=(x2+6x+9)(x2-6x+9),
=(x+3)2(x-3)2.