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arXiv · 1209.2920

Refinements of the inequalities between Neuman-Sandor, arithmetic, contra-harmonic and quadratic means

Yu-Ming Chu·Miao-Kun Wang
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Abstract

In this paper, we prove that the inequalities $\alpha [1/3 Q(a,b)+2/3 A(a,b)]+(1-\alpha)Q^{1/3}(a,b)A^{2/3}(a,b) 0$ with $a\neq b$ if and only if $\alpha\leq (3-3\sqrt[6]{2}\log(1+\sqrt{2}))/[(2+\sqrt{2}-3\sqrt[6]{2})\log(1+\sqrt{2})]=0.777...$, $\beta\geq 4/5$, $\lambda\leq (6-6\sqrt[6]{2}\log(1+\sqrt{2}))/(7-6\sqrt[6]{2}\log(1+\sqrt{2}))=0.274...$, and $\mu\geq 8/25$. Here, $M(a,b)$, $A(a,b)$, $C(a,b)$, and $Q(a,b)$ denote the Neuman-S\'{a}ndor, arithmetic, contra-harmonic, and quadratic means of $a$ and $b$, respectively.

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Yu-Ming Chu, Miao-Kun Wang. 2012-09-13. Refinements of the inequalities between Neuman-Sandor, arithmetic, contra-harmonic and quadratic means. https://arxiv.org/abs/1209.2920

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