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Difference between revisions of "2009 IMO Problems/Problem 4"

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==Solution==
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==See Also==
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{{IMO box|year=2009|num-b=3|num-a=5}}

Latest revision as of 01:17, 19 November 2023

Problem

Let $ABC$ be a triangle with $AB=AC$. The angle bisectors of $\angle CAB$ and $\angle ABC$ meet the sides $BC$ and $CA$ at $D$ and $E$, respectively. Let $K$ be the incentre of triangle $ADC$. Suppose that $\angle BEK=45^\circ$. Find all possible values of $\angle CAB$.

Authors: Jan Vonk and Peter Vandendriessche, Belgium, and Hojoo Lee, South Korea

Solution

This problem needs a solution. If you have a solution for it, please help us out by adding it.

See Also

2009 IMO (Problems) • Resources
Preceded by
Problem 3 		1 • 2 • 3 • 4 • 5 • 6 Followed by
Problem 5
All IMO Problems and Solutions
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