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MathNet 2014 Question 36

Math Olympiad Vault · MathNet 2014

Question 36

Given is a $\triangle ABC$ with incircle $k$ touching the sides $BC$ and $CA$ in points $P$ and $Q$ respectively. Let denote with $J$ the center of the excircle at side $AB$ in $\angle ABC$ and with $T$ – the second intersection point of the circumcircles of $\angle JBP$ and $\angle JAQ$. Prove that the circumcircle of $\angle ABT$ touches $k$.