MathDB
JBMO TST Bosnia and Herzegovina 2022 P3

Source: JBMO TST Bosnia and Herzegovina 2022

May 21, 2022
JBMO TSTgeometrycircumcirclenational olympiad

Problem Statement

Let ABCABC be an acute triangle. Tangents on the circumscribed circle of triangle ABCABC at points BB and CC intersect at point TT. Let DD and EE be a foot of the altitudes from TT onto ABAB and ACAC and let MM be the midpoint of BCBC. Prove: A) Prove that MM is the orthocenter of the triangle ADEADE. B) Prove that TMTM cuts DEDE in half.