Refinements of Huygens- and Wilker- type inequalities

Ling Zhu; Zhengjie Sun; Ling Zhu; Zhengjie Sun

doi:10.3934/math.2020191

AIMS Mathematics

2020, Volume 5, Issue 4: 2967-2978. doi: 10.3934/math.2020191

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Research article

Refinements of Huygens- and Wilker- type inequalities

Ling Zhu ^{1
,
,},
Zhengjie Sun ^2,3

1.
Department of Mathematics, Zhejiang Gongshang University, Hangzhou, Zhejiang, China
2.
Department of Mathematics, Hong Kong Baptist University, Hong Kong
3.
Shanghai Key Laboratory for Contemporary Applied Mathematics, School of Mathematical Sciences, Fudan University, Shanghai, China

Received: 22 November 2019 Accepted: 11 March 2020 Published: 19 March 2020
MSC : Primary 26D15; Secondary 42A10

In this paper we give some refinements and sharpness of the Huygens- and Wilker- type inequalities, and show a proof of the second conjecture by Chen and Chueng in [10].
Citation: Ling Zhu, Zhengjie Sun. Refinements of Huygens- and Wilker- type inequalities[J]. AIMS Mathematics, 2020, 5(4): 2967-2978. doi: 10.3934/math.2020191

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Abstract

In this paper we give some refinements and sharpness of the Huygens- and Wilker- type inequalities, and show a proof of the second conjecture by Chen and Chueng in [10].

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