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MathNet 2006 — Part 04 Question 190

Math Olympiad Vault · MathNet 2006 — Part 04

Question 190

In acute triangle $ABC$, segments $AD$, $BE$, and $CF$ are its altitudes, and $H$ is its orthocenter. Circle $\omega$, centered at $O$, passes through $A$ and $H$ and intersects sides $AB$ and $AC$ again at $Q$ and $P$ (other than $A$), respectively. The circumcircle of triangle $OPQ$ is tangent to segment $BC$ at $R$. Prove that $CR/BR = ED/FD$.