Given an acute triangle inscribed in with and symmedian point . The tangents at of intersect at . Prove that the line , two circumcircles of triangles and pass through the same point.
Solution
Let be the midpoint of the minor arc of and be the intersection point of the tangents at of . We will show that and lie on .
Indeed, we have
so passes through . Similarly, passes through . Now, let be the center of , and we will show that .
From here, since is the center of circle then and , it follows that lie on the same line parallel to . Since intersects at other than , then but so . On the other hand, since is the center of so . According to the familiar result, , so which finishes the proof.
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