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Formalized Mathematics

(a computer assisted approach)

Editor-in-Chief: Matuszewski, Roman

4 Issues per year

SCImago Journal Rank (SJR) 2016: 0.207
Source Normalized Impact per Paper (SNIP) 2016: 0.315

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Volume 24, Issue 1


Altitude, Orthocenter of a Triangle and Triangulation

Roland Coghetto
Published Online: 2016-08-31 | DOI: https://doi.org/10.1515/forma-2016-0003


We introduce the altitudes of a triangle (the cevians perpendicular to the opposite sides). Using the generalized Ceva’s Theorem, we prove the existence and uniqueness of the orthocenter of a triangle [7]. Finally, we formalize in Mizar [1] some formulas [2] to calculate distance using triangulation.

MSC: 51M04; 03B35

Keywords: Euclidean geometry; trigonometry; altitude; orthocenter; triangulation; distance

MML : identifier: EUCLID13; version: 8.1.04 5.36.1267


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About the article

Received: 2015-12-30

Published Online: 2016-08-31

Published in Print: 2016-03-01

Citation Information: Formalized Mathematics, Volume 24, Issue 1, Pages 27–36, ISSN (Online) 1898-9934, DOI: https://doi.org/10.1515/forma-2016-0003.

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© by Roland Coghetto. This work is licensed under the Creative Commons Attribution-ShareAlike 3.0 License. BY-SA 3.0

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