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28 real bitangents: Dedicated to Ian Porteus

Published online by Cambridge University Press:  14 November 2011

W. L. Edge
W. L. Edge
Affiliation:
Nazareth House, Hillhead, Bonnyrigg, Midlothian EH19 2JF, Scotland, U.K.
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Abstract

Although all the coefficients in the equation of a plane algebraic curve may be real numbers, it by no means follows that the equations of all its bitangents are real. But Plücker perceived that this could happen for the 28 bitangents of a nonsingular plane quartic. Where can this be observed in a body of 28 explicit linear equations? This modest note affords an example.

Type
Research Article
Information
Proceedings of the Royal Society of Edinburgh Section A: Mathematics , Volume 124 , Issue 4 , 1994 , pp. 729 - 736
Copyright
Copyright © Royal Society of Edinburgh 1994

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