Confirm that f and g are inverses by showing that f(g(x)) = x and g(f(x)) = x.

F(x)=
g(x)=

1. f(g(x))=x
f(g(x)) means to put g(x) wherever you find x in f(x).

f(g(x)) =
f(g(x)) =
Reverse the dominator and simplify with x-1

f(g(x)) =
f(g(x)) =  = x

So we proved that f(g(x))=x

2. g(f(x))=x
g(f(x)) means to put f(x) wherever you find x in g(x).

g(f(x)) = 
g(f(x)) =
g(f(x)) = 

Reverse the dominator and simplify with x+3

g(f(x))= 

So we proved that g(f(x))=x

Because f(g(x)) = x and g(f(x)) = x f and g are inverse.