MathDB
(n+1) cos(pi/n+1)-n cos(pi/n)>1 for all natural n>1

Source:

November 3, 2010
inequalitiestrigonometryinequalities unsolved

Problem Statement

Prove the inequality (n+1)cos⁡πn+1−ncos⁡πn>1(n + 1)\cos\frac{\pi}{n + 1}- n\cos\frac{\pi}{n}> 1 for all natural numbers n≥2.n \ge 2.
Back to ProblemsView on AoPS