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2001 IMO Shortlist Problems/G2

Problem

Consider an acute-angled triangle $ABC$. Let $P$ be the foot of the altitude of triangle $ABC$ issuing from the vertex $A$, and let $O$ be the circumcenter of triangle $ABC$. Assume that $\angle C \geq \angle B + 30^{\circ}$. Prove that $\angle A + \angle COP < 90^{\circ}$.

Solution

See 2001 IMO 1 page. https://artofproblemsolving.com/wiki/index.php/2001_IMO_Problems/Problem_1

Resources

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