- Research Article
- Open Access
On the Strengthened Jordan's Inequality
- Jian-Lin Li1Email author and
- Yan-Ling Li1
https://doi.org/10.1155/2007/74328
© J.-L. Li and Y.-L. Li. 2007
Received: 21 July 2007
Accepted: 22 November 2007
Published: 6 February 2008
Abstract
The main purpose of this paper is to present two methods of sharpening Jordan's inequality. The first method shows that one can obtain new strengthened Jordan's inequalities from old ones. The other method shows that one can sharpen Jordan's inequality by choosing proper functions in the monotone form of L'Hopital's rule. Finally, we improve a related inequality proposed early by Redheffer.
Keywords
- Proper Function
- Related Inequality
- Monotone Form
Authors’ Affiliations
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Copyright
This article is published under license to BioMed Central Ltd. 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.
