A Spherical Pythagorean Theorem

Maraner, Paolo
September 2010
Mathematical Intelligencer;Sep2010, Vol. 32 Issue 3, p46
Academic Journal
The article discusses the issue of extending the geometrical Pythagorean theorem to non-Euclidean geometries, with specific emphasis on the more intuitive spherical geometry. In apparent contradiction with the statement that the Pythagorean proposition is equivalent to Euclid's parallel postulate, the author shows that such an extension not only exists, but also yields a deeper insight into the classical theorem.


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