MathDB
tangent bisects AD, where AD is diameter (2014 From Tasks to Tasks, p9 Ukr)

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May 3, 2021
geometrybisects segment

Problem Statement

On a circle with diameter ABAB we marked an arbitrary point CC, which does not coincide with AA and BB. The tangent to the circle at point AA intersects the line BCBC at point DD. Prove that the tangent to the circle at point CC bisects the segment ADAD.