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MathNet 2009-part-03 — 175 problems (EN–VI) Question 113

Math Olympiad Vault · MathNet 2009-part-03 — 175 problems (EN–VI)

Question 113

Segment $BD$ is an angle bisector in a triangle $ABC$ (point $D$ lies on segment $AC$). Line $BD$ intersects the circumcircle $\Omega$ of triangle $ABC$ at points $B$ and $E$. Circle $\omega$ with diameter $DE$ intersects $\Omega$ at points $E$ and $F$. Prove that the line symmetrical to $BF$ with respect to $BD$ contains a median of triangle $ABC$.

(L. Emelyanov)