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MathNet 2011 Question 46

Math Olympiad Vault · MathNet 2011

Question 46

In a triangle let $O$ be the circumcenter, $I$ the incenter, and $r$ the inradius. The perpendicular bisector of $OI$ meets the circumcircle at $L$, and line $LI$ meets it again at $M$. Prove $IM=2r$.