For this case we have the following functions:
[tex]g (n) = 2n + 4\\h (n) = - 3n ^ 3 + 4[/tex]
We must find [tex](g_ {o} h) (n).[/tex] By definition of composition of functions we have:
[tex](g_ {o} h) (n) = g (h (n))[/tex]
So, we have:
[tex]g (h (n)) = 2 (-3n ^ 3 + 4) + 4 = -6n ^ 3 + 8 + 4 = -6n ^ 3 + 12[/tex]
Finally we have to:
[tex](g_ {o} h) (n) = - 6n ^ 3 + 12[/tex]
ANswer:
[tex](g_ {o} h) (n) = - 6n ^ 3 + 12[/tex]