Johann Rahn^{[1]} (Latinised form Rhonius) (10 March 1622 – 25 May 1676) was a Swiss mathematician who is credited with the first use of the division symbol, ÷ (obelus)^{[2]} and the therefore sign, ∴.^{[3]} The symbols were used in Teutsche Algebra, published in 1659. John Pell collaborated with Rahn in this book, which contains an example of the Pell equation. It is uncertain whether Rahn or Pell was responsible for introducing the symbols. Rahn was also, it seems, mayor of the city of Zurich in 1655.^{[according to whom?]}
Books
Literature
- R. Acampora Johann Heinrich Rahn und seine Teutsche Algebra, in R. Gebhardt (Herausgeber) Visier- und Rechenbücher der frühen Neuzeit, Schriften des Adam-Ries-Bundes Annaberg-Buchholz 19, 2008, S. 163–178
- Moritz Cantor: Rahn, Johann Heinrich . In: General German Biography (ADB). Volume 27, Duncker & Humblot, Leipzig, 1888, pp. 174 f
- Noel Malcolm, Jacqueline Stedall John Pell (1611–1685) and His Correspondence with Sir Charles Cavendish: The Mental World of an Early Modern Mathematician, Oxford University Press, Oxford, 2005
- Christoph Scriba John Pell's English Edition of J. H. Rahn 's Teutsche Algebra, in: R. S. Cohen (Herausgeber) For Dirk Struik, Reidel: Dordrecht 1974, S. 261–274
- Jacqueline Stedall A Discourse Concerning Algebra: English Algebra to 1685, Oxford University Press, Oxford, 2002
See also
References
- general
- Cajori, Florian. A History of Mathematical Notations. 2 volumes. Lasalle, Illinois: The Open Court Publishing Co., 1928–1929 vol. 2, page 211.
- citations
- ^ The dictionary of biographical reference By Lawrence Barnett Phillips. pg 775
- ^ Such as on pg 16; Teutsche Algebra. Pg 16
- ^ Such as on pg 53; Teutsche Algebra. Pg 53