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On the Strengthened Jordan's Inequality

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.

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Correspondence to Jian-Lin Li.

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Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License (https://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Li, JL., Li, YL. On the Strengthened Jordan's Inequality. J Inequal Appl 2007, 074328 (2008). https://doi.org/10.1155/2007/74328

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  • DOI: https://doi.org/10.1155/2007/74328

Keywords

  • Proper Function
  • Related Inequality
  • Monotone Form