Double-click on the movie to PLAY.

Click once to PAUSE.

RELOAD the page or double-click to return to the START of the movie.

Method C1

Here we start with the multiplier 1.2 but gradually increase it to 2, ie we consider the locus of P as r changes from 1.2 to 2 in the relationship AP = r x BP. Again, we assume AB = 2 units.

Before running the movie it is worth asking
- what happens to the locus (ie the size of the circle) as r increases from 1.2 to 2 ?
- what is the diameter of the circle when r = 2 ?

After running the movie, it is worth asking
- what would happen to the locus if we made r larger and larger?
- what would happen to the locus if r was less than 1.2 ?

On the next page we consider values of r from a maximum of 4 to a minimum of 1/4 (ie 0.25).