Euclidean Conics

Part of the Problem Books in Mathematics book series (PBM)


From 15.D we know there are three possible cases of Euclidean affine conics: the ellipse, the hyperbola and the parabola. Only the parabola does not have a center; it has a single axis of (orthogonal) symmetry and a vertex. The ellipse and the hyperbola have a center and two axes of orthogonal symmetry; the ellipse has four vertices (with the exception of the circle), and the hyperbola has two. The equations, in an appropriate orthonormal basis, are
$$\begin{array}{l} \frac{{{x^2}}}{{{a^2}}} + \frac{{{y^2}}}{{{b^2}}} - 1 = 0(ellipse),\;\frac{{{x^2}}}{{{a^2}}} - \frac{{{y^2}}}{{{b^2}}} - 1 = 0(hyperbola),\\ {y^2} - 2px = 0(parabola). \end{array} $$


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Marcel Berger 1984

Authors and Affiliations

  1. 1.U.E.R. de Mathematique et InformatiqueUniversité Paris VIIParis, Cedex 05France
  2. 2.Centre National de la Recherche ScientifiqueParisFrance
  3. 3.P.U.K.GrenobleFrance

Personalised recommendations