For this case we have the following functions:
[tex]f (x) = 4-x ^ 2\\g (x) = 6x[/tex]
We must find[tex](g-f) (3)[/tex].
By definition we have to:
[tex](g-f) (x) = g (x) -f (x)[/tex]
So:
[tex](g-f) (x) = 6x- (4-x ^ 2) = 6x-4 + x ^ 2[/tex]
So, we have to for[tex]x = 3:[/tex]
[tex](g-f) (3) = 6 (3) -4+ (3) ^ 2[/tex]
Answer:
The correct option is C
[tex]6 (3) -4+ (3) ^ 2[/tex]