Skip to main content
Log in

On the cubic of Napoleon

  • Published:
Journal of Geometry Aims and scope Submit manuscript

Abstract

This paper explores properties of an interesting cubic from the Euler pencil of analagmatic cubics associated to a triangle. Our arguments are algebraic and use a combination of trilinear coordinates and complex numbers. We study its basic properties with emphasis on ways how to recognise this curve in various geometric configurations. Since this cubic is closely tied with the so called Napoleon configuration of a scalene triangle, we named it the Napoleon cubic.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. H. S. M. Coxeter,Some applications of trilinear coordinates, Linear Algebra and Its Appl.226–228 (1995), 375–388.

    Google Scholar 

  2. H. M. Cundy andC. F. Parry,Some cubic curves associated with a triangle, J. Geom.53 (1995), 41–66.

    Google Scholar 

  3. R. Deaux,Introduction to the geometry of complex numbers, Ungar Publ. Co., New York, 1956.

    Google Scholar 

  4. H. L. Dorwart,The Neuberg cubic: A nostalgic look, California Math.3 (1978), 31–38.

    Google Scholar 

  5. R. H. Eddy andR. Fritsch,The conics of Ludwig Kiepert: A comprehensive lesson in the geometry of the triangle, Math. Mag.67 (1994), 188–205.

    Google Scholar 

  6. L. Hahn,Complex numbers and geometry, MAA, Washington, 1994.

    Google Scholar 

  7. R. Honsberger,Episodes in nineteenth and twentieth century Euclidean geometry, MAA, Washington, 1995.

    Google Scholar 

  8. R. A. Johnson,Advanced Euclidean Geometry, Dover Publ., New York, 1964.

    Google Scholar 

  9. Clark Kimberling,Central points and central lines in the plane of a triangle, Math. Mag.67 (1994), 163–187.

    Google Scholar 

  10. H. Martini,On the theorem of Napoleon and related topics, Math. Semesterber.43 (1996), 47–64.

    Google Scholar 

  11. Frank Morley andF. V. Morley,Inversive Geometry, Chelsea Publ. Co., New York, 1954.

    Google Scholar 

  12. Jean Baptiste Joseph Neuberg,Cours de Géométrie Analytique, A. Herman, Paris, 1908.

    Google Scholar 

  13. Guido M. Pinkernell,Cubic curves in the triangle plane, J. Geom.55 (1996), 141–161.

    Google Scholar 

  14. Pablo Rubio,Cubic lines relative to a triangle, J. Geom.34 (1989), 152–171.

    Google Scholar 

  15. I. M. Yaglom,Complex numbers in geometry, Academic Press, New York, 1968.

    Google Scholar 

  16. P. Yff,Two families of cubics associated with a triangle, In Eves' Circles (Ed.: J. M. Anthony), MAA, Washington, 1993.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Cerin, Z. On the cubic of Napoleon. J Geom 66, 55–71 (1999). https://doi.org/10.1007/BF01225672

Download citation

  • Received:

  • Revised:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01225672

Keywords

Navigation