# Graphing Polar Equations:

• Jun 8th 2009, 04:32 PM
Neversh
Graphing Polar Equations:
I don't seem to get how to graph them. Currently trying to understand how to graph: r = 3cos(2X)
• Jun 8th 2009, 09:58 PM
craig
Quote:

Originally Posted by Neversh
I don't seem to get how to graph them. Currently trying to understand how to graph: r = 3cos(2X)

When graphing polar coordinates it's important to remember that r is the length of the line, and x is the angle in radians, measured anti-clockwise from the positive "x-axis".

What I do is use values for x such as $0, \frac{\pi}{8}, \frac{\pi}{4}, \frac{3\pi}{8}$ etc, and plot the r values that these give me.

When I have a good amount of points I then join them up. Remember your graphs will most likely be circles or spirals.

Also a graphic calculator is invaluable for graphing polar coordinates if you have one.