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Let $ABC$ be an acute-angled triangle with $AB < AC$ ...

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August 8, 2015
geometrycircumcircle

Problem Statement

Let ABCABC be an acute-angled triangle with AB<ACAB < AC, and let points DD and EE be chosen on the side ACAC and BCBC respectively in such a way that AD=AE=ABAD = AE = AB. The circumcircle of ABEABE intersects the line ACAC at AA and FF and the line DEDE at EE and PP. Prove that PP is the circumcentre of BDFBDF.