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Geo with angle 60 degrees

Source: Oral Moscow geometry olympiad 2023 10-11.1

April 20, 2023

geometry

Problem Statement

In triangle ABC

\angle ABC=60^{o}

and

O

is the center of the circumscribed circle. The bisector

BL

intersects the circumscribed circle at the point

W

. Prove that

OW

is tangent to

(BOL)