The equation of a limacon is
[tex]\begin{gathered} r(\theta)=a+b\cos\theta \\ \text{ or } \\ r(\theta)=a+b\sin\theta \end{gathered}[/tex]I'll use a = 1 and b = 2. This means b > a then the limacon will have an inner loop. Using Geogebra to plot the graphs we get:
As we can see, the blue limacon is the limacon with sin and the green limacon is the limacon with cos