The curve is
,
.
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.
\
Consider
.


Consider
.

Substitute
in
and
.

Substitute
in
and
.

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

Since the slope is not defined, there is no vertical tangent lines to the given curve.
\ \ \
Graph of the curve
,
is :

Observe the graph of the curve notice that, the curve has horizontal tangent lines at the points
and
.
The points on the curve where the tangent line is horizontal are
and
.
There is no vertical tangent lines to the given curve.