Lighthouse Curves

A bunch of straight lines rotates around two points in a plane with constant angular velocities. (An apt metaphore of two lighthouses was invented by R. K. Guy of the University of Calgary.)

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If at each lighthouse the beams are equally spaced through 360°, the pairwise intersections of the beams form regular polygons: regular triangles for three beams, squares for four beams, etc. (This is known as the Lighthouse Theorem.)

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Copyright © 1996-2017 Alexander Bogomolny

... to be continued ...

|Activities| |Contact| |Front page| |Contents| |Geometry| |Store|

Copyright © 1996-2017 Alexander Bogomolny


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