Dynamic Geometry 1468: Steiner's Theorem, Triangle, Circumradius, Inradius, Sum of Exradii, Step-by-step Illustration
The figure below shows a triangle ABC with the circumradius R, the inradius r and the exradii ra, rb, rc. Prove that \(r_a+r_b+r_c=4 \cdot R+r\) .
Static Diagram of Geometry 1468: Steiner's Theorem
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Interactive step-by-step animation using GeoGebra
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Ten problems: 1411-1420
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Circle
Triangle Centers
Circumradius, Circumcenter
Inradius, Incenter, Incircle
Exradius, Excenter, Excircle
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