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MathNet 2020 — Math Olympiad Vault — Part 03 Question 125

Math Olympiad Vault · MathNet 2020 — Math Olympiad Vault — Part 03

Question 125

In an acute triangle $ABC$, $I$ is the incenter and $|AC|+|AI|=|BC|$. Prove that $\angle BAC=2\angle ABC$.

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