\ \
The polar equation is and
.
If the point has Cartesian coordinates
and polar coordinates
, then
.
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 .
.
Find .
Consider .
Apply derivative on each side with respect to .
.
.
Substitute and
.
Find slope at the point .
Slope of the tangent line is .
Slope of the tangent line is . \ \