Basic Technical Mathematics, 11th Edition

21.11 Curves in Polar Coordinates

• Curve Sketched from Equations • Plotting Polar Coordinate Curves • Calculator Display of Polar Curves • Polar Curve Generated by Data

The basic method for finding a curve in polar coordinates is the same as in rectangular coordinates. We assume values of the independent variable—in this case, $\theta$ —and then find the corresponding values of the dependent variable r. These points are then plotted and joined, thereby forming the curve that represents the relation in polar coordinates.

Before using the basic method, it is useful to point out that certain basic curves can be sketched directly from the equation. This is done by noting the meaning of each of the polar coordinate variables, r and $\theta \hspace{0.17em}.\hspace{0.17em}$ This is illustrated ...