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arXiv · 2108.07213

Reversion Porisms in Conics

Lorenz Halbeisen·Norbert Hungerbühler·Marco Schiltknecht
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Abstract

We give a projective proof of the butterfly porism for cyclic quadrilaterals and present a general reversion porism for polygons with an arbitrary number of vertices on a conic. We also investigate projective properties of the porisms.

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Lorenz Halbeisen, Norbert Hungerbühler, Marco Schiltknecht. 2021-08-04. Reversion Porisms in Conics. https://arxiv.org/abs/2108.07213

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