The
purpose of this applet is to illustrate the relation between a point
on the unit circle, its coordinates and the angle between the x-axis
and the line through the origin and the point. Use it as follows:
Drag the point
around the unit circle, clockwise or counterclockwise, as many times
as you want. As you do so, the following should happen:

- The coordinates
of the point will be updated.
- The value of
the angle between the x-axis and the line through the origin and
the point will show only if you have selected to display it. In
this case, it will be displayed in the chosen units (degrees or
radians).
- The point will
be in green if it corresponds to a positive angle, otherwise it
will be red.