How do you determine the shape of a limaçon from the polar equation?

1 Answer
Apr 13, 2015

A polar graph that is a limacon has a formula similar to #r= a +- bcostheta# or #r= a +- bsintheta#
where #a<b# or #a>b#

Case1: #a<b#
Here you have a limacon with an inner loop
Example: #r = 2 + 4costheta#

Case2: #a>b#
In this case, the limacon does not have an inner loop.
Example: #r = 5 + costheta#