Haruki's Theorem

From HandWiki
Short description: Geometry Theorem
Illustration of Haruki's Theorem:
s1s2s3s4s5s6=1

Haruki's Theorem says that given three intersecting circles that only intersect each other at two points that the lines connecting the inner intersecting points to the outer satisfy:

s1s3s5=s2s4s6

where s1,s2,s3,s4,s5,s6 are the measure of segments connecting the inner and outer intersection points.[1][2][3]

The theorem is named after the Japanese mathematician Hiroshi Haruki.

References

  1. Wisstein, Eric. "Haruki's Theorem". Wolfram MathWorld. http://mathworld.wolfram.com/HarukisTheorem.html. Retrieved 19 August 2015. 
  2. Bogomolny, Alexander. "Cut the Knot". http://www.cut-the-knot.org/proofs/HarukiTheorem.shtml. Retrieved 19 August 2015. 
  3. Ross Honsberger: Episodes in Nineteenth and Twentieth Century Euclidean Geometry. MAA, 1995, p. 144-146