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

m (Problem)
Line 4: Line 4:
  
 
''Authors: Jan Vonk and Peter Vandendriessche, Belgium, and Hojoo Lee, South Korea''
 
''Authors: Jan Vonk and Peter Vandendriessche, Belgium, and Hojoo Lee, South Korea''
 +
 +
==Solution==
 +
{{solution}}
 +
 +
==See Also==
 +
 +
{{IMO box|year=2009|num-b=3|num-a=5}}

Revision as of 00:17, 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