Section: Book 04: Circles: Inscription and Circumscription

The 4th Book of the "Elements" is devoted to the solution of problems, chiefly relating to the inscription and circumscription of regular polygons and circles. It contains 16 propositions proven purely geometrically.

The focus of this book lies on compass and ruler constructions. It contains the following constructions:

  1. Subsection: Definitions from Book 4
  2. Subsection: Propositions from Book 4

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  1. Byrne, O.: "The First Six Books of the Elements of Euclid, in Which Coloured Diagrams and Symbols are used Instead of Letters", London William Pickering, 1847