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MathNet 2013 Question 53

Math Olympiad Vault · MathNet 2013

Question 53

Inside a circle $c$ there are circles $c_1$, $c_2$ and $c_3$ which are tangent to $c$ at points $A$, $B$ and $C$ correspondingly, which are all different. Circles $c_2$ and $c_3$ have a common point $K$ in the segment $BC$, circles $c_3$ and $c_1$ have a common point $L$ in the segment $CA$, and circles $c_1$ and $c_2$ have a common point $M$ in the segment $AB$. Prove that the circles $c_1$, $c_2$ and $c_3$ intersect in the center of the circle $c$.