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IMO Shortlist
1977 IMO Shortlist
4
4
Part of
1977 IMO Shortlist
Problems
(1)
Describe all closed bounded figures Phi
Source:
9/20/2010
Describe all closed bounded figures
Φ
\Phi
Φ
in the plane any two points of which are connectable by a semicircle lying in
Φ
\Phi
Φ
.
geometry
circle
Convexity