MathDB
Largest Area

Source: 1984 National High School Mathematics League, Exam Two, Problem 3

February 22, 2020
geometry

Problem Statement

In ABC\triangle ABC, PP is a point on BCBC. FAB,EAC,PF//CA,PE//BAF\in AB,E\in AC,PF//CA,PE//BA. If SABC=1S_{\triangle ABC}=1, prove that at least one of SBPF,SPCE,SPEAFS_{\triangle BPF},S_{\triangle PCE},S_{PEAF} is not less than 49\frac{4}{9}.