x^3+2x^2-5x-6=?
问题描述：
x^3+2x^2-5x-6=?
答
x^3+2x^2-5x-6
=(x^3+x^2)+(x^2-5x-6)
=x^2(x+1)+(x-6)(x+1)
=(x^2+x-6)(x+1)
=(x+3)(x-2)(x+1)