Unutar trokuta ABCABC s duljinama stranica a,b,ca, b, c i odgovarajućim kutovima α,β,γ\alpha, \beta, \gamma postoje točke PP i QQ takve da vrijedi BPC=CPA=APB=120°,\measuredangle BPC = \measuredangle CPA = \measuredangle APB = 120°, BQC=60°+α,CQA=60°+β,AQB=60°+γ.\measuredangle BQC = 60° + \alpha, \quad \measuredangle CQA = 60° + \beta, \quad \measuredangle AQB = 60° + \gamma.

Dokažite da vrijedi jednakost (AP+BP+CP)3AQBQCQ=(abc)2.(|AP| + |BP| + |CP|)^3 \cdot |AQ| \cdot |BQ| \cdot |CQ| = (abc)^2.