f
(
x
)
=
3
x
Write
f
(
x
)
=
3
x
as an equation.
y
=
3
x
Interchange the variables.
x
=
3
y
Solve for
y
.
.
y
=
3
x
Replace the
y
with
f
−
1
(
x
)
to show the final answer.
f
−
1
(
x
)
=
3
x
Verify if
f
−
1
(
x
)
=
3
x
is the inverse of
f
(
x
)
=
3
x
.
...
f
−
1
(
x
)
=
3
x