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IMO 1996 - Shortlisted problems Question 12

IMO Shortlist · IMO 1996 - Shortlisted problems

Question 12

G3 (GBR) Let $ABC$ be an acute-angled triangle with $BC\gt CA$. Let $O$ be the circumcenter, $H$ its orthocenter, and $F$ the foot of its altitude $CH$. Let the perpendicular to $OF$ at $F$ meet the side $CA$ at $P$. Prove that $\angle FHP=\angle BAC$.
Possible second part: What happens if $|BC|\le|CA|$ (the triangle still being acute-angled)?