MathDB
n-variable inequality

Source: All-Russian MO 2023 Final stage 10.8

April 23, 2023
inequalitiesalgebra

Problem Statement

Given is a real number a(0,1)a \in (0,1) and positive reals x0,x1,,xnx_0, x_1, \ldots, x_n such that xi=n+a\sum x_i=n+a and 1xi=n+1a\sum \frac{1}{x_i}=n+\frac{1}{a}. Find the minimal value of xi2\sum x_i^2.