Refinements and Sharpening of some Huygens and Wilker Type Inequalities

Wei-Dong Jiang¹, Qiu-Ming Luo² and Feng Qi^{3, 4,}

¹Department of Information Engineering, Weihai Vocational University, Weihai, Shandong, China

²Department of Mathematics, Chongqing Normal University, Chongqing City, China

³College of Mathematics, Inner Mongolia University for Nationalities, Tongliao City, Inner Mongolia Autonomous Region, China

⁴Department of Mathematics, College of Science, Tianjin Polytechnic University, Tianjin City, China;Institute of Mathematics, Henan Polytechnic University, Jiaozuo City, Henan Province, China

Cite this paper:
Wei-Dong Jiang, Qiu-Ming Luo and Feng Qi. Refinements and Sharpening of some Huygens and Wilker Type Inequalities. Turkish Journal of Analysis and Number Theory. 2014; 2(4):134-139. doi: 10.12691/tjant-2-4-6

Abstract

In the article, some Huygens and Wilker type inequalities involving trigonometric and hyperbolic functions are refined and sharpened.

Keywords:
refinement sharpening Huygens inequality Wilker inequality trigonometric function hyperbolic function

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