The Rolling Circles when the Ratio of Radii is 2:1.

Construct a hypocycloid where the ratio of the radii is 2:1.

Click HERE for a GSP file.

The hypocycloids will be line segments through the center of the fixed circle.

The hypotrophoids will each be an ellipse.

Construct an epicycloid where the ratio of the radii is 2:1.

Click HERE for a GSP file.