Respuesta :

Answer:

(f-g)(x) = x^4 - x^3 - 4x^2 - 3

Step-by-step explanation:

(f-g)(x) = x^4 - x^2 + 9 - (x^3 + 3x^2 + 12)

(f-g)(x) = x^4 - x^2 + 9 - x^3 - 3x^2 - 12

(f-g)(x) = x^4 - x^3 - 4x^2 - 3