x^3+2x^2-10x-20

问题描述:

x^3+2x^2-10x-20

=x^2(x+2)-10(x+2)
=(x+2)(x^2-10)

x^3+2x^2-10x-20
=x^2(x+2) -10(x+2)
=(x+2)(x^2-10)