Journal of Inequalities and Applications
Volume 2010 (2010), Article ID 362548, 14 pages
doi:10.1155/2010/362548
Research Article

On Jordan Type Inequalities for Hyperbolic Functions

R. Klén, M. Visuri, and M. Vuorinen

Department of Mathematics, University of Turku, 20014 Turku, Finland

Received 28 January 2010; Accepted 29 April 2010

Academic Editor: Andrea Laforgia

Copyright © 2010 R. Klén et al. 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.

Abstract

This paper deals with some inequalities for trigonometric and hyperbolic functions such as the Jordan inequality and its generalizations. In particular, lower and upper bounds for functions such as (sinx)/x and x/sinhx are proved.