Type a function of [math]\theta[/math] into the input box, use [math]t[/math] in the place of [math]\theta[/math].[br]Negative values of [math]r[/math] can be shown by ticking the check box.[br]You can see how the curve is generated by altering the input boxes max[math]\theta[/math] and min[math]\theta[/math].

Can you predict the shape of the curve?[br]Created by Dr GJ Daniels.