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Topic:
Harmonic set of points internal/external division NEED HELP
Replies:
4
Last Post:
Nov 7, 2012 8:07 AM




Re: Harmonic set of points internal/external division NEED HELP
Posted:
Sep 18, 2011 2:12 PM



You're right, it's not plain English. I remember scratching my head on this one.
I'm enclosing a GSP sketch that will illustrate it. If you don't have GSP, write me back.
If AC means the distance between points A and C, BD means the distance between B and D and so on, and if a distance in the direction of the ray AB is positive and a distance in the direction of the ray BA is negative, then a harmonic set is one where
AC AD  =   CB DB
See also http://mathworld.wolfram.com/HarmonicRange.html



