Division of an Angle Bisector by the Incenter

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Let ABC be a triangle with incenter I. Let AA' be the bisector of with A' on BC. Then
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Contributed by: Jay Warendorff (March 2011)
Open content licensed under CC BY-NC-SA
Snapshots
Details
Problem 1.17(b) in V. Prasolov, Problems in Plane and Solid Geometry, Vol. 1, Plane Geometry [PDF], (D. Leites, ed. and trans.).
Permanent Citation
"Division of an Angle Bisector by the Incenter"
http://demonstrations.wolfram.com/DivisionOfAnAngleBisectorByTheIncenter/
Wolfram Demonstrations Project
Published: March 7 2011