ISL 2018 G3
A circle of radius 1 is given. A collection of triangles is called good, if the following conditions hold: (i) each triangle from is inscribed in ; (ii) no two triangles from have a common interior point. Determine all positive real numbers such that, for each positive integer , there exists a good collection of triangles, each of perimeter greater than . (South Africa)
Dataset text NuminaMath olympiads. Quoted with source.
Official text: IMO 2018 Shortlist booklet, page 8.
Solutions
Official solution Solution 1 by the IMO Problem Selection Committee
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