## Real Analysis Exchange

### The Inequality of Milne and its Converse, III

#### Abstract

The discrete version of Milne’s inequality and its converse states that \begin{equation*} (*)\quad \sum_{j=1}^n\frac{w_j}{1-p_j^2} \leq \sum_{j=1}^n\frac{w_j}{1-p_j} \sum_{j=1}^n\frac{w_j}{1+p_j} \leq \Bigl(\sum_{j=1}^n\frac{w_j}{1-p_j^2} \Bigr)^2 \end{equation*} is valid for all $w_j>0$ $(j=1,...,n)$ with $w_1+\dots+w_n=1$ and $p_j\in (-1,1)$ $(j=1,...,n)$. We present new upper and lower bounds for the product $\sum w/(1-p) \sum w/(1+p)$. In particular, we obtain an improvement of the right-hand side of $(*)$. Moreover, we prove a matrix analogue of our double-inequality.

#### Article information

Source
Real Anal. Exchange, Volume 44, Number 1 (2019), 89-100.

Dates
First available in Project Euclid: 27 June 2019

https://projecteuclid.org/euclid.rae/1561622434

Digital Object Identifier
doi:10.14321/realanalexch.44.1.0089

Mathematical Reviews number (MathSciNet)
MR3951336

Zentralblatt MATH identifier
07088965

Subjects
Primary: 26D15: Inequalities for sums, series and integrals
Secondary: 15A45: Miscellaneous inequalities involving matrices

#### Citation

Alzer, Horst; Kovačec, Alexander. The Inequality of Milne and its Converse, III. Real Anal. Exchange 44 (2019), no. 1, 89--100. doi:10.14321/realanalexch.44.1.0089. https://projecteuclid.org/euclid.rae/1561622434