The equation of conic is .
The general form of a conic is .
Here ,
,
,
,
and
.
Find .
The conic is an ellipse.
\The angle is .
Substitute ,
and
in the above equation.
Assume that the angle lies on second quadrant.
\Observe the diagram :
\.
Find and
.
Half angle identity : .
Half angle identity : .
.
Find equations for and
.
.
Substitute and
in the above equation.
.
.
Substitute and
in the above equation.
.
Substitute and
in equation (1).
The standard form of equation is .