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Several sharp inequalities involving (hyperbolic) tangent, tanc, cosine, and their reciprocals

  • Wen-Hui Li und Bai-Ni Guo EMAIL logo
Veröffentlicht/Copyright: 6. Dezember 2024
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Abstract

In the paper, in view of two monotonicity rules for the ratios of two functions and of two Maclaurin power series expansions, the authors establish several sharp inequalities involving (hyperbolic) tangent, tanc, cosine, and their reciprocals.


This paper is dedicated to Professor Dr. Feng Qi for his retirement in 2025


Acknowledgement

The authors appreciate the anonymous referees for their careful reading, valuable comments, and helpful suggestions to the original version of this paper.

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Received: 2024-02-08
Accepted: 2024-07-22
Published Online: 2024-12-06
Published in Print: 2024-12-15

© 2024 Mathematical Institute Slovak Academy of Sciences

Heruntergeladen am 17.12.2025 von https://www.degruyterbrill.com/document/doi/10.1515/ms-2024-0104/pdf?lang=de
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