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Find the locus of Miquel point

Source: KoMaL A.748

May 18, 2019
geometryincircleMiquel point

Problem Statement

The circles Ω\Omega and ω\omega in its interior are fixed. The distinct points A,B,C,D,EA,B,C,D,E move on Ω\Omega in such a way that the line segments AB,BC,CD,DEAB,BC,CD,DE are tangents to ω\omega .The lines ABAB and CDCD meet at point PP, the lines BCBC and DEDE meet at QQ . Let RR be the second intersection of the circles BCPBCPand CDQCDQ, other than CC. Show that RR moves either on a circle or on a line.