Polar Reciprocals: A Cardiod and A Parabola
Point P' traces out the pedal curve - a Cardiod - of the circle A with pedal point C on circle A. Point P is the inverse of point P' with respect to the circle C (referred to as reciprocals). The locus of point P is a Parabola. The Cardiod and the Parabola are polar reciprocals.