问题
解答题
分解因式:
(1)x3+x2-4x-4
(2)25xn-10xn+1+xn+2.
答案
(1)x3+x2-4x-4
=x3-4x+x2-4
=x(x2-4)+(x2-4)
=(x2-4)(x+1)
=(x+2)(x-2)(x+1);
(2)25xn-10xn+1+xn+2
=xn(x2-10x+25)
=xn(x-5)2.
分解因式:
(1)x3+x2-4x-4
(2)25xn-10xn+1+xn+2.
(1)x3+x2-4x-4
=x3-4x+x2-4
=x(x2-4)+(x2-4)
=(x2-4)(x+1)
=(x+2)(x-2)(x+1);
(2)25xn-10xn+1+xn+2
=xn(x2-10x+25)
=xn(x-5)2.