To find (f•g)(x) we need to solve the product of the expressions for each of the functions, this way:
[tex]\begin{gathered} (f\cdot g)(x)=f(x)\cdot g(x) \\ =(x+4)\cdot(x-1) \\ =x^2-x+4x-4 \\ =x^2+3x-4 \end{gathered}[/tex]The obtained is a polynomic function. In this kind of functions, the domain has no restrictions, it means that the domain of this function is All real numbers.
