问题
解答题
把下列各式分解因式.
(1)x3-9x
(2)xy-5x-y+5.
答案
(1)x3-9x
=x(x2-9)
=x(x+3)(x-3);
(2)xy-5x-y+5
=(xy-5x)+(-y+5)
=x(y-5)-(y-5)
=(y-5)(x-1).
把下列各式分解因式.
(1)x3-9x
(2)xy-5x-y+5.
(1)x3-9x
=x(x2-9)
=x(x+3)(x-3);
(2)xy-5x-y+5
=(xy-5x)+(-y+5)
=x(y-5)-(y-5)
=(y-5)(x-1).