问题
解答题
因式分
(1)ax2-16ay2.
(2)-2a3+12a2-18a;
(3)4+12(x-y)+9(x-y)2.
答案
(1)ax2-16ay2,
=a(x2-16y2),
=a(x+4y)(x-4y);
(2)-2a3+12a2-18a,
=-2a(a2-6a+9),
=-2a(a-3)2;
(3)4+12(x-y)+9(x-y)2,
=[2+3(x-y)]2,
=(3x-3y+2)2.