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MathNet 2022-part-01 — 197 problems (EN–VI) Question 19

Math Olympiad Vault · MathNet 2022-part-01 — 197 problems (EN–VI)

Question 19

Let $I$ be the incenter of triangle $ABC$. The incircle of $ABC$ is tangent to side $BC$ at $D$. Let $P$ and $Q$ be points on rays $IB$ and $IC$ respectively such that $\angle IAP = \angle CAD$ and $\angle IAQ = \angle BAD$. Prove that $AP = AQ$.