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circumcircle of KTH_1 tangent to BC (2016 Kyiv City MO 11.4)

Source:

September 6, 2020
geometrycircumcircletangentorthocenter

Problem Statement

The median AMAM is drawn in the acute-angled triangle ABCABC with different sides. Its extension intersects the circumscribed circle ww of this triangle at the point PP. Let AH1A {{H} _ {1}} be the altitude ΔABC\Delta ABC, HH be the point of intersection of its altitudes. The rays MHMH and PH1P {{H} _ {1}} intersect the circle ww at the points KK and TT, respectively. Prove that the circumscribed circle of ΔKTH1\Delta KT {{H} _ {1}} touches the segment BCBC.
(Hilko Danilo)