first we write both functions:
g (a) = root (a-5) -2
f (a) = 5 + a ^ 2
We now make the composition of functions:
(g or f) (a) = g (f (a))
g (f (a)) = root ((5 + a ^ 2) -5) -2
Rewriting:
g (f (a)) = root (5 + a ^ 2-5) -2
g (f (a)) = root (a ^ 2) -2
g (f (a)) = lal-2
answer:
option 3:
g (a) = root (a-5) -2
f (a) = 5 + a ^ 2