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AP bisects BC, BD // CE, 3 circumcircles related

Source: 1st Final Mathematical Cup 2019 FMC , juniors p1

October 6, 2020
geometrycircumcircle

Problem Statement

Let ABCABC be a triangle and let D,ED, E are points on its circumscribed circle, such that DD lies on arc AB,EAB, E lies on arc ACAC (smaller arcs) and BDCEBD \parallel CE . Let the point F be the intersection of the lines DADA and CECE, and the intersection of the lines EAEA and BDBD is GG. Let PP be the second intersection of the circumscribed circles of ABG\vartriangle ABG and ACF\vartriangle ACF. Prove that the lineAP AP passes through the mid point of the side BCBC.