A‰ne-regular hexagons of extreme areas inscribed in a centrally symmetric convex body
نویسنده
چکیده
Let M be a planar centrally symmetric convex body. If H is an a‰ne regular hexagon of the smallest (the largest) possible area inscribed in M, then M contains (respectively, the interior of M does not contain) an additional pair of symmetric vertices of the a‰neregular 12-gon TH whose every second vertex is a vertex of H. Moreover, we can inscribe in M an octagon whose three pairs of opposite vertices are vertices of an a‰ne-regular hexagon H and the remaining pair is a pair of opposite vertices of TH . A corollary concerns packing M with its three homothetical copies. Another corollary is that the unit disk of any Minkowski plane contains three points in distances at least 1þ ffiffiffi
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