问题
解答题
因式分解:
(1)3xy2-27x;
(2)4ab(a-b)-a3.
答案
(1)3xy2-27x
=3x(y2-9)
=3x(y+3)(y-3);
(2)4ab(a-b)-a3
=4a2b-4ab2-a3
=-a(4b2-4ab+a2)
=-a(2b-a)2.
因式分解:
(1)3xy2-27x;
(2)4ab(a-b)-a3.
(1)3xy2-27x
=3x(y2-9)
=3x(y+3)(y-3);
(2)4ab(a-b)-a3
=4a2b-4ab2-a3
=-a(4b2-4ab+a2)
=-a(2b-a)2.