The parametric equations are
and
.
Find the points at which the tangent is horizontal.
\For Horizontal tangent:
.
Consider
.
Apply derivative on each side with respect to
.

.
Equate
to
.

.
Horizontal tangents are at
.
Find the point of horizontal tangency.
\At
:
.
.
At
, the point is
.
At
:
.
.
At
, the point is
.
Horizontal tangent line occur at
and
.
For vertical tangent:
.
Consider
.
Apply derivative on each side with respect to
.


.
Equate
to
.

.
At
:
.
.
At
, the point is
.
Vertical tangent line occur at
.
Graph:
\Graph the parametric equations
and
.
.
Horizontal tangent line occur at
and
.
Vertical tangent line occur at
.