r1998

Let O be the circumcenter; Oa, Ob, Oc the reflections of O on the sides; Oab, Oac the reflections of Oa on AB, AC, and define analogously Obc, Oba, Oca, Ocb.
1) ABC and the triangle A'B'C' bounded by OabOac, ObcOba, OcaOcb are orthologic, with a center at the Kosnita point Ks
2) The ninecircles of AOabOac, BObcOba, COcaOcb concur at the point X(52)
 
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