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MathNet 2017-part-03 — 176 problems (EN–VI) Question 1

Math Olympiad Vault · MathNet 2017-part-03 — 176 problems (EN–VI)

Question 1

Let $ABC$ be a triangle and $\Gamma$ its circumcircle. Let $\omega_{A}$ be the circle internally tangent to $(AB)$, $(AC)$ and to $\Gamma$. Denote by $T_{A}$ the point of tangency of $\Gamma$ with $\omega_{A}$. Define $T_{B}$ and $T_{C}$ similarly.
Prove that $\left(AT_{A}\right),\left(BT_{B}\right)$ and $\left(CT_{C}\right)$ are concurrent.