Here,

And we need to find the value of f(g(x)) when x = 5 . It means , we need to find f(g(5)) .
So first we need to find g(5) and for that we plug 5 for x in g(x). That is ,

So the value of g(5) is 1 .
Now we have f(g(5)) = f(1) . And f(1) is

So the value of f(g(5)) =1