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MathNet 2013 Question 99

Math Olympiad Vault · MathNet 2013

Question 99

Let ABC be a triangle. Let Γ₁ be the circle through B tangent to side AC at A, and Γ₂ the circle through C tangent to side AB at A. Denote their second intersection by D. Line AD meets the circumcircle of ABC again at E. Prove that D is the midpoint of AE.

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