9514 1404 393
Answer:
C. 3x² +24
Step-by-step explanation:
Use the given function definitions and simplify.
[tex]g(f(x))=g\left(\dfrac{1}{3}x^2+4\right)\\\\=9\left(\dfrac{1}{3}x^2+4\right)-12\\\\=3x^2+36-12\\\\\boxed{g(f(x))=3x^2+24}\qquad\textbf{matches C}[/tex]