Three nonnegative real numbers satisfy a,b,c satisfy a2≤b2+c2,b2≤c2+a2 and c2≤a2+b2. Prove the inequality
(a+b+c)(a2+b2+c2)(a3+b3+c3)≥4(a6+b6+c6).
When does equality hold? inequalitiesinequalities solvedSides of a triangle3-variable inequalitySymmetric inequalityJapan2001