Parallelograms inscribed in a curve having a circle as π/2-isoptic
Andrzej Miernowski
Annales UMCS, Mathematica, Tome 62 (2008), p. 105-111 / Harvested from The Polish Digital Mathematics Library
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Jean-Marc Richard observed in [7] that maximal perimeter of a parallelogram inscribed in a given ellipse can be realized by a parallelogram with one vertex at any prescribed point of ellipse. Alain Connes and Don Zagier gave in [4] probably the most elementary proof of this property of ellipse. Another proof can be found in [1]. In this note we prove that closed, convex curves having circles as π/2-isoptics have the similar property.

Publié le : 2008-01-01
EUDML-ID : urn:eudml:doc:268006 
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     title = {Parallelograms inscribed in a curve having a circle as $\pi$/2-isoptic},
     journal = {Annales UMCS, Mathematica},
     volume = {62},
     year = {2008},
     pages = {105-111},
     zbl = {1182.52004},
     language = {en},
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Andrzej Miernowski. Parallelograms inscribed in a curve having a circle as π/2-isoptic. Annales UMCS, Mathematica, Tome 62 (2008) pp. 105-111. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_v10062-008-0012-4/

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