因式分解 (1)4-12(x-y)+9(x-y)2; (2)2a(x2+1)2-8ax2.
问题描述:
因式分解
(1)4-12(x-y)+9(x-y)2;
(2)2a(x2+1)2-8ax2.
答
(1)4-12(x-y)+9(x-y)2,
=22-2×2×3(x-y)+[3(x-y)]2,
=[2-3(x-y)]2,
=(2-3x+3y)2;
(2)2a(x2+1)2-8ax2,
=2a[(x2+1)2-4x2],
=2a(x2+1-2x)(x2+1+2x),
=2a(x-1)2(x+1)2.