Dynamic Geometry 1473: Kosnita's Theorem, Triangle, Four Circumcenters, Concurrent Line, Step-by-step Illustration

The dynamic geometry figure below shows a triangle ABC with the circumcenter O. If O_A, O_B, and O_C, are the circumcenters of triangles BOC, AOC, and AOB, respectively, prove that lines AO_A, BO_B, and CO_C are concurrent.

See solution below

Static Diagram of Geometry Problem 1473

Kosnita's Theorem, Triangle, Four Circumcenters, Concurrent Line, Step-by-step Illustration, iPad Apps

Poster of the Kornita's Theorem 1473 using iPad Apps

Dynamic Geometry 1473: Kosnita Theorem, Four Circumcenters, Concurrent Line, Step-by-step Illustration Using GeoGebra, iPad Apps

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Interactive step-by-step animation using GeoGebra

This step-by-step interactive illustration was created with GeoGebra.

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