A Best Possible Double Inequality for Power Mean

We answer the question: for any p,q∈ℝ with p≠q and p≠-q, what are the greatest value λ=λ(p,q) and the least value μ=μ(p,q), such that the double inequality Mλ(a,b)<Mp(a,b)Mq(a,b)<Mμ(a,b) holds for all a,b>0 with a≠b? Where Mp(a,b) is the pth power mean of two positive numbers a and b....

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Bibliographic Details
Main Authors: Yong-Min Li, Bo-Yong Long, Yu-Ming Chu
Format: Article
Language:English
Published: Hindawi Limited 2012-01-01
Series:Journal of Applied Mathematics
Online Access:http://dx.doi.org/10.1155/2012/379785
Description
Summary:We answer the question: for any p,q∈ℝ with p≠q and p≠-q, what are the greatest value λ=λ(p,q) and the least value μ=μ(p,q), such that the double inequality Mλ(a,b)<Mp(a,b)Mq(a,b)<Mμ(a,b) holds for all a,b>0 with a≠b? Where Mp(a,b) is the pth power mean of two positive numbers a and b.
ISSN:1110-757X
1687-0042