### Video Summary:

The Polar Coordinate System
Based on
A point called the pole, and
A ray called the polar axis, usually drawn in the direction of the positive x-axis. The ordered pair P(r, ) gives the polar coordinates of point P. Equations such as
r = 3 sin , r = 2 + cos , or r = ,
are examples of polar equations where r and are the variables.
The simplest equation for many types of curves turns out to be a polar equation.
Evaluate r in terms of until a pattern appears.
Technology Note When graphing in polar coordinates,
make sure the calculator is in polar mode.