Function : For any input of
, we get only one output for
.
The equation is
.
Solve the above equation for
.

Subtract
from each side.

Divide each side by
.
.
An input
.
Substitute
in
.


.
An input
.
Substitute
in
.



.
For any input of
, we get only one output for
.
So, the equation
defines
as a function of
.
The equation
defines
as a function of
.