Calculus/Polar Differentiation

Differential calculus edit

We have the following formulae:

 
 

To find the Cartesian slope of the tangent line to a polar curve   at any given point, the curve is first expressed as a system of parametric equations.

 
 

Differentiating both equations with respect to   yields

 
 

Dividing the second equation by the first yields the Cartesian slope of the tangent line to the curve at the point   :