Which expression represents the composition [g o f o h] (x) for the functions below?

f (x) = 5x - 4

g (x) = 5x3

h (x) = 3x

5 (15x - 4) 3

(75x - 20) 3

5 (5x - 4) 3

675x3 - 4

First plug h into g (x).

g (x) = 5x^3

g (3x) = 5 (3x) ^3

g (3x) = 5*27x^3

g (3x) = 135x^3

Now plug 135x^3 into the f function.

5 (135x^3) - 4

675x^3 - 4

The last one is correct.