Chapter 4 - Polynomial and Rational Functions - 4.1 Polynomial Functions and Models - 4.1 Assess Your Understanding - Page 185: 45

$f(x)=x^3-x^2-12x$

If $c$ is a zero of a function with multiplicity $b$ then $(x-c)^b$ is a “factor” of the function. We are given that the degree is $3$, and the zeros are $-3$, $0$ and $4$, hence $f(x)=a(x+3)(x)(x-4)=a(x^3-x^2-12x)$ If $a=1$, the function is $f(x)=x^3-x^2-12x$