Dragutin Svrtan and Darko Veljan, Non-Euclidean versions of some classical triangle inequalities,
Forum Geometricorum, 12 (2012) 197--209.
Abstract.
In this paper we recall with short proofs of some classical triangle inequalities, and prove corresponding
non-Euclidean, i.e., spherical and hyperbolic versions of these inequalities. Among them are the well
known Euler's inequality, Rouché's inequality (also called ``the fundamental triangle inequality"),
Finsler - Hadwiger's inequality, isoperimetric inequality and others.
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