Contents

Cut the Knot

A beautiful mathematics website with hundreds of geometric constructions, problems, puzzles and important theorems usually well illstruated.

Cut-the-knot.org

Scan through the glossary of math terms to find an idea, or search the geometry index. Also consider using an advance Google search where you specify the site “cut-the-knot.org” and put in a geometric term.

Tip

Try a Google search like this

triangle site:http://www.cut-the-knot.org

Replace the word triangle with any basic geometry term to see an expansive array of ideas.

Project Ideas

There is so much interesting geometry at the cut-the-knot, it’s hard to list a Top Ten or anything like that. Click on a few of the links below to see what kinds of things are possible. Definitely spend some time kicking around cut-the-knot before you decide on your final project idea.

  1. Apollonian circles or just Apollonius in general

  2. An old Japanese theorem with circles inscribed in polygons.

  3. Search for anything related to Archimedes

  4. Sangaku and Egyptian Triangles

  5. Anything related to Ceva, for example, Cevian triangles

  6. The Buttefly Theorem

  7. Morley’s mirale

Regular Polygons