AIMS Mathematics, 2020, 5(4): 2967-2978. doi: 10.3934/math.2020191

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Refinements of Huygens- and Wilker- type inequalities

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

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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