Lester's theorem

From Wikipedia, the free encyclopedia

In Euclidean plane geometry, Lester's theorem, named after June Lester, states that in any scalene triangle, the two Fermat points, the nine-point center, and the circumcenter are concyclic.

See also

  • Dao-Moses circle
  • Parry circle

References

  • Clark Kimberling, "Lester Circle", Mathematics Teacher, volume 89, number 26, 1996.
  • June A. Lester, "Triangles III: Complex triangle functions", Aequationes Mathematicae, volume 53, pages 435, 1997.
  • Michael Trott, "Applying GroebnerBasis to Three Problems in Geometry", Mathematica in Education and Research, volume 6, pages 1528, 1997.
  • Ron Shail, "A proof of Lester's Theorem", Mathematical Gazette, volume 85, pages 225232, 2001.
  • John Rigby, "A simple proof of Lester's theorem", Mathematical Gazette, volume 87, pages 444452, 2003.
  • J.A. Scott, "On the Lester circle and the Archimedean triangle", Mathematical Gazette, volume 89, pages 498500, 2005.
  • Michael Duff, "A short projective proof of Lester's theorem", Mathematical Gazette, volume 89, pages 505506, 2005.
  • Stan Dolan, "Man versus Computer", Mathematical Gazette, volume 91, pages 469480, 2007.
  • Yiu, Paul (2010), "The circles of Lester, Evans, Parry, and their generalizations", Forum Geometricorum 10: 175–209, MR 2868943 .

External links


This article is issued from Wikipedia. The text is available under the Creative Commons Attribution/Share Alike; additional terms may apply for the media files.