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MathNet 2005 — Part 02 Question 68

Math Olympiad Vault · MathNet 2005 — Part 02

Question 68

Let $H$ be the orthocenter of $\triangle ABC$, $M$ be the midpoint of $AB$ and $H_1$ and $H_2$ be the feet of the perpendiculars from $H$ to the inner and the outer bisector of $\measuredangle ACB$, respectively. Prove that the points $H_1$, $H_2$ and $M$ are colinear.