IMOC 2018 G4 (parallel wanted, circumcircles, incenter, symmetrics related)
Source: https://artofproblemsolving.com/community/c6h1740825p11314688
March 22, 2020
geometrycircumcircleincenterparallel
Problem Statement
Given an acute with incenter . Let be the symmetric point with respect to the midpoint of and is the foot of . If and the circumcircle of vartriangle intersect at and intersects the circumcircle of at . Furthermore, are tangent points of the incircle and is the another intersection of the circumcircles of . Show that .
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