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MathNet 2012 Question 33

Math Olympiad Vault · MathNet 2012

Question 33

Let $\triangle ABC$ be an acute triangle. Let $\omega$ be a circle whose center $L$ lies on the side $BC$. Suppose that $\omega$ is tangent to $AB$ at $B_1$ and to $AC$ at $C_1$. Suppose also that the circumcenter $O$ of the triangle $ABC$ lies on the shorter arc $B_1C_1$ of $\omega$.
Prove that the circumcircle of $ABC$ and $\omega$ meet at two points.

Illustrative configuration only.

Question illustration