a,b,c lengths of the sides of a triangle (IMO SL 1987-P6)
Source:
August 19, 2010
rearrangement inequalitythree variable inequalitytriangle inequalityInequalityIMO Shortlist
Problem Statement
Show that if are the lengths of the sides of a triangle and if , then
\frac{a^n}{b+c} + \frac{b^n}{c+a} +\frac{c^n}{a+b} \geq \left(\dfrac 23 \right)^{n-2}S^{n-1} \forall n \in \mathbb N Proposed by Greece.