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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 23, Issue 2


Morley’s Trisector Theorem

Roland Coghetto
Published Online: 2015-08-13 | DOI: https://doi.org/10.1515/forma-2015-0007


Morley’s trisector theorem states that “The points of intersection of the adjacent trisectors of the angles of any triangle are the vertices of an equilateral triangle” [10]. There are many proofs of Morley’s trisector theorem [12, 16, 9, 13, 8, 20, 3, 18]. We follow the proof given by A. Letac in [15].

MSC: 51M04; 03B35

Keywords: Euclidean geometry; Morley’s trisector theorem; equilateral triangle

MML: identifier: EUCLID11; version:


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About the article

Received: 2015-03-26

Published Online: 2015-08-13

Published in Print: 2015-06-01

Citation Information: Formalized Mathematics, Volume 23, Issue 2, Pages 75–79, ISSN (Online) 1898-9934, DOI: https://doi.org/10.1515/forma-2015-0007.

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© by Roland Coghetto. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License. BY-NC-ND 3.0

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