因式分解6a^2b-9ab^3+3ab;a^3-6a^2-7a;(x^2+x)^2-(x+1)^2
问题描述：
因式分解6a^2b-9ab^3+3ab;a^3-6a^2-7a;(x^2+x)^2-(x+1)^2
答
6a^2b-9ab^3+3ab;
=3ab(2a-3b²+1)
a^3-6a^2-7a;
=a(a²-6a-7)
=a(a+1)(a-7)
(x^2+x)^2-(x+1)^2
=x²(x+1)^2-(x+1)^2
=(x+1)²(x²-1)
=(x+1)²(x-1)(x+1)
答
6a^2b-9ab^3+3ab=3ab(2a-3b^2+1)a^3-6a^2-7a=a(a^2-6a-7)=a(a+1)(a-7)(x^2+x)^2-(x+1)^2=(x^2+x+x+1)(x^2+x-x-1)=(x^2+2x+1)(x^2-1)=(x+1)^2(x+1)(x-1)=(x+1)^3(x-1)