Answer:
[tex]x^{2} -2x-8[/tex]
Step-by-step explanation:
(f g)(x) is equal to f(x) times g(x). So you just need to multiply both of the equations together. Use the foil method to multiply (x+2)(x-4)
[tex](fg)(x)=f(x)*g(x)\\\\(fg)(x)=(x+2)(x-4)\\\\(fg)(x)=x^{2} -4x+2x-8\\\\(fg)(x)=x^{2} -2x-8\\[/tex]
I have attached an image to better explain the foil method
