Reversion Porisms in Conics

Year 2021, , 371 - 382, 29.10.2021

Lorenz Halbeısen , Norbert Hungerbühler , Marco Schiltknecht

https://doi.org/10.36890/iejg.979088

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.

Keywords

Porisms, butterfly theorems, reversion map

References

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