The equation is
and the angle is
.
Rotation equations for
and
:
and
.
Substitute
.
and 
and 
and
.
Substitute
and
in
.

.
The equation in the
-plane is
.
The equation in the
-plane is
.
Compare the equation with general conic equation
.
Here
and
.
For this equation:
\
, the conic is parabola.
The equation in the
-plane is
.
The conic is parabola.