Geometry Problem 1469: Triangle, Circumradius, Inradius, Midpoints, Arcs, Sum of Distances, Step-by-step Illustration

The figure below shows a triangle ABC with the circumradius R, the inradius r. If \(d, e, f\) are the distances from the midpoints of arcs AB, AC, BC to the sides BC, BC, and AC, respectively, prove that \(d+e+f=2(R+r)\).

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Static Diagram of Geometry Problem1469

Dynamic Geometry 1469: Steiner Theorem, Triangle, Circumradius, Inradius, Sum of Exradii, Step-by-step Illustration Using GeoGebra, iPad Apps


Poster of the Dynamic Geometry 1469 using iPad Apps

Poster Dynamic Geometry 1469: Triangle, Circumradius, Inradius, Midpoints, Arcs, Sum of Distances, Step-by-step Illustration Using GeoGebra, iPad Apps

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