VMO 1986 Problem 5

Find all n > 1 such that ( $x_1^2$ + $x_2^2$ + ... + $x_n^2$ ) ≥ $x_n$ ( $x_1$ + $x_2$ + ... + $x_{n-1}$ ) for all real $x_i$ .

Community text Kalva (prase.cz mirror). Quoted with source.

Solutions

No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.

Locator vn-vmo/1986/p5 · Tag 5VKC573J4Q · Edit this page on GitHub · Keys: j next, k previous