International Journal of Mathematics and Mathematical Sciences
Volume 2012 (2012), Article ID 597490, 9 pages
Research Article

On Huygens' Inequalities and the Theory of Means

Department of Mathematics, Babeş-Bolyai University, Strada Kogălniceanu no. 1, 400084 Cluj-Napoca, Romania

Received 24 March 2012; Accepted 20 August 2012

Academic Editor: Mowaffaq Hajja

Copyright © 2012 József Sándor. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


By using the theory of means, various refinements of Huygens' trigonometric and hyperbolic inequalities will be proved. New Huygens' type inequalities will be provided, too.