Welcome to Wilson Stothers' Cabri and Conics Pages.

These pages were written to accompany a Geometry course at the University of Glasgow.
They may be of interest to others, especially Open University M203 students -
see M203 Page for some important differences of content.

In the conics section, the algebraic and geometric approaches to conics and duality
are outlined and shown to be equivalent.
On the Cabri Conics Menu page, there is a toolbar of Cabri macros.
To use the macros, you will need the Cabri II geometry program -
you can get a demo version via the introduction page.
Although the Classical Theorems pages contain Cabri .fig files, they can be used without Cabri.
They indicate the connection between the results, with much emphasis on duality.
Throughout, there are links to biographies of some of the key figures in the subject.

• Main Conics Page
  • Conics - the classical definition
  • Ideal points for the euclidean plane
  • Homogeneous coordinates for RP²
  • Tangents - a geometrical approach
  • A geometric approach to poles, polars and duality
  • An algebraic approach to poles, polars and duality
  • Conics as sections of a cone.
• Introduction to Cabri
  • The Cabri Conics Menu
  • Classical Theorems illustrated by Cabri
  • Cabri Links