The polar equation is
and
.
If the point
has Cartesian coordinates
and polar coordinates
, then
and
.
Substitute
in polar coordinates.
.
.
The slope of the tangent line is derivative of the function.
\Apply chain rule of derivatives :
.
First find
.
\
Consider
.
Apply derivative on each side with respect to
.

Apply product rule of derivatives:
.



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

Apply product rule of derivatives:
.



.
.
Substitute
and
.

.
The slope of the tangent line of polar equation
is
.
The curve equation is
.
Substitute
in polar coordinates.
.
.
Consider
.


.
Consider
.




.
.
Substitute
and
.

.
The slope of the tangent line of polar equation
is
.
The slope of the tangent line of polar equation
is
.
The slope of the tangent line of polar equation
is
.
The product of slopes is
\
.
The tangent lines of
and
are perpendicular to each other.
Therefore, the curves
and
are perpendicular. \ \
The curves
and
are perpendicular.