The functions are
and
.
Find the points on the curve where the tangent line is horizontal or vertical.
\Slope of the horizontal tangent line is 0.
\Slope of the vertical tangent line is
.
Find the slope of the curve.
\Consider
.
Apply derivative on each side with respect to
.

.
Consider
.
Apply derivative on each side with respect to
.

.
Slope of the tangent line is first derivative of the curve.
\Slope of the curve is
.
Substitute
and
.
.
Slope of the tangent line is
.
Slope of the horizontal tangent line is 0.
\\
\


.
Substitute
in
and
.
.
.
The points on the curve where the tangent line is horizontal are
.
Slope of the vertical tangent line is
.
\
\




.
Substitute
in
and
.
.
.
The points on the curve where the tangent line is vertical are
.
To check the result, graph the curve.
\The graph of the curve
and
is :

Observe the graph of the curve notice that, the curve has horizontal tangent lines at the points
and vertical tangent lines at
.
The points on the curve where the tangent line is horizontal are
.
The points on the curve where the tangent line is vertical are
.