A screen capture from my new Graphics Calculator - A HP40gs.
I also downloaded an emulator so I can run all the same calculations on the PC.
This plot is done by setting the parametric equations to x1(t)=cos(t), y1(t)=sin(3*t),
Just enter them and press plot!
Link for more info http://www.hphomeview.com/ and
http://en.wikipedia.org/wiki/Lissajous_curve
http://en.wikipedia.org/wiki/Australian_Broadcasting_Corporation