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MathNet 2018-part-05 — 181 problems (EN–VI) Question 75

Math Olympiad Vault · MathNet 2018-part-05 — 181 problems (EN–VI)

Question 75

Let $ABC$ be a triangle inscribed in circle $(O)$ with incenter $I$. The lines $IB$ and $IC$ intersect $(O)$ again at $J$ and $L$. The circumcircle $(\omega)$ of triangle $IBC$ meets $CA$, $AB$ again at $E$, $F$. Prove that $EL$ and $FJ$ intersect on $(\omega)$.