Inversion Development

These are the html java applets for the talk:

Getting a Definition

Starting with a look at the reflection transformation, we develop a definition of a transformation of (a punctured) plane based on a circle.
  1. Reflections: a reminder of a distance perserving transformation.
  2. Revisiting Reflections: a new characteriztion to motivate inversion in a circle.
  3. A "new construction" for a reflection: a new characteriztion to motivate inversion in a circle.
  4. Looking for inversion: using the reflection model on a circle.
  5. Why P doesn't matter: just as in the line example, A' is independent of our choice for P.
  6. More why P doesn't matter: just as in the line example, A' is independent of our choice for P.

    Having a definition, we look at ways to construct the transformation.

  7. Characterizing a circle: looking at different locus characterizations for a circle.
  8. Constructing a tangent from a point to a circle: we'll use this to ge an easy compass and straight-edge construction of an inversion.
  9. Another construction of an inversion:
  10. A compass only construction of an inverse point: Just for fun.

Playing with the Definition

Having the definition and constructions, we explore inversions of lines and circles.
  1. inversion on a the circle of inversion
  2. inversion on a line through the center of inversion
  3. inversion on a point on a line (not through the center of inversion)
  4. Inverting a line (not through O)
  5. inversion on a point on a circle
  6. inversion of a circle
  7. Inversion and Similar Triangles
  8. Proving inverting a line (not through O)
  9. Revisit inverting concentric circles

Steiner's Alternative


Last Modified: Wed Dec 7 20:17:10 PST 2005