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More variations on the Steiner-Lehmus theme

Published online by Cambridge University Press:  14 February 2019

Sadi Abu-Saymeh
Affiliation:
P. O. Box 963708, 11196 Amman, Jordan e-mail: ssaymeh@yahoo.com
Mowaffaq Hajja
Affiliation:
P. O. Box 566, 21163 Al-Husun, Irbid, Jordan e-mail: mowhajja@yahoo.com

Extract

The celebrated Steiner-Lehmus theorem states that if the internal bisectors of two angles of a triangle are equal, then the triangle is isosceles. In other words, if P is the incentre of triangle ABC, and if BP and CP meet the sides AC and AB at B′and C′, respectively, then

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Articles
Copyright
Copyright © Mathematical Association 2019 

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References

1. Hajja, M., A short trigonometric proof of the Steiner-Lehmus theorem, Forum Geom. 8 (2008) pp. 3942.Google Scholar
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