Geodesic
Some remarks on Ptolemy's theorem and its applications
The Teaching of Mathematics, XXIII (2020) no. 1, p. 57 .

Voir la notice de l'article provenant de la source eLibrary of Mathematical Institute of the Serbian Academy of Sciences and Arts

The subject matter of this article is a beautiful theorem developed by Ptolemy (about 100-178) in Chapters 10 and 11 of the first book of Almagest, the Great Collection of Astronomy in 13 books. In order to solve astronomical problems, Ptolemy used mathematical tools to calculate the length of the chord in the circle of radius $60$ as a function of the central angle. The application of Ptolemy's theorem is presented by giving some interesting examples. The paper analyzes the results in solving problems from the competitions in which Ptolemy's theorem is applied.
Classification : 97G40, G44
Keywords: Ptolemy's theorem, cyclic quadrilateral. 
@article{TM2_2020_XXIII_1_a6,
     author = {Miljan Kne\v{z}evi\'c and Dragana Savi\'c},
     title = {Some remarks on {Ptolemy's} theorem and its applications},
     journal = {The Teaching of Mathematics},
     pages = {57 },
     publisher = {mathdoc},
     volume = {XXIII},
     number = {1},
     year = {2020},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TM2_2020_XXIII_1_a6/}
}
TY  - JOUR
AU  - Miljan Knežević
AU  - Dragana Savić
TI  - Some remarks on Ptolemy's theorem and its applications
JO  - The Teaching of Mathematics
PY  - 2020
SP  - 57 
VL  - XXIII
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/TM2_2020_XXIII_1_a6/
LA  - en
ID  - TM2_2020_XXIII_1_a6
ER  - 
%0 Journal Article
%A Miljan Knežević
%A Dragana Savić
%T Some remarks on Ptolemy's theorem and its applications
%J The Teaching of Mathematics
%D 2020
%P 57 
%V XXIII
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/TM2_2020_XXIII_1_a6/
%G en
%F TM2_2020_XXIII_1_a6
Miljan Knežević; Dragana Savić. Some remarks on Ptolemy's theorem and its applications. The Teaching of Mathematics, XXIII (2020) no. 1, p. 57 . http://geodesic.mathdoc.fr/item/TM2_2020_XXIII_1_a6/