问题
解答题
因式分
(1)x2-4;
(2)x3-9x;
(3)x3+4x2+4x.
答案
(1)x2-4=(x+2)(x-2);
(2)x3-9x
=x(x2-9)
=x(x+3)(x-3);
(3)x3+4x2+4x
=x(x2+4x+4)
=x(x+2)2.
因式分
(1)x2-4;
(2)x3-9x;
(3)x3+4x2+4x.
(1)x2-4=(x+2)(x-2);
(2)x3-9x
=x(x2-9)
=x(x+3)(x-3);
(3)x3+4x2+4x
=x(x2+4x+4)
=x(x+2)2.