the ellipse and its evolute
and the distance problem:
updating Apollonius

by Frederick Hartmann and Robert Jantzen [2004]

• introduction with animation and article links
  MAA Convergence 2004:
   "Apollonius's Ellipse and Evolute Revisited - The Alternative Approach to the Evolute"
• maple worksheet [updated frenetellipse2009.mw][frenetellipse2021-short.mw]
• html export of original maple worksheet

This project is a fond memory of my friendship with Fritz Hartmann who left us too soon in 2021 [obituary].

The ellipse plot with its evolute and family of normal lines is a pretty design. Extracting only the simple figure from the article is done here:

• ellipseevoluteplot2022.mw [Maple worksheet producing images below]
• ellipseevoluteplot2022.pdf  [Export of this worksheet showing image parameters]
• ellipseevolute.jpg  [red and blue image below]
• ellipseevoluteBW.jpg  [black and white image below]

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