ISL 2009 G1
Let be a triangle with . The angle bisectors of and meet the sides and in and , respectively. Let be the incenter of triangle . Suppose that . Find all possible values of .
Official text Transcription from NuminaMath olympiads, checked word for word against the official paper. Quoted with source.
Official text: IMO 2009 Shortlist booklet, page 10.
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60^{\circ} \text{ or } 90^{\circ}
Solutions
Official solution Solution 1 by the IMO Problem Selection Committee
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