Polar Rose Grapher
You can enter any equation here, but this was set up to look at rose curves. You can type in number for t (theta) or k (dilation) or can type in numbers. Just remember to put the angle you are analyzing in parenthesis, so 2cos3t would need to be entered as 2*cos(3*t)
This graph was adapted from here: https://www.geogebra.org/material/show/id/upbPEhNK