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Inequality holding for n reals always.

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December 6, 2010
inequalitiesinequalities unsolved

Problem Statement

We consider nn real variables xi(1in)x_i(1 \le i \le n), where nn is an integer and n2n \ge 2. The product of these variables will be denoted by pp, their sum by ss, and the sum of their squares by SS. Furthermore, let α\alpha be a positive constant. We now study the inequality psSαps \le S\alpha. Prove that it holds for every nn-tuple (xi)(x_i) if and only if α=n+12\alpha=\frac{n+1}{2}