Answer :
For this case we must find
[tex](f + g) (x).[/tex]
By definition we have to:
[tex](f + g) (x) = f (x) + g (x)[/tex]
We have the following functions:
[tex]f (x) = 5x ^ 3-2\\g (x) = 2x + 1[/tex]
Now, applying the given definition, we have:
[tex](f + g) (x) = 5x ^ 3-2 + 2x + 1\\(f + g) (x) = 5x ^ 3 + 2x-1[/tex]
Answer:
[tex](f + g) (x) = 5x ^ 3 + 2x-1[/tex]