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On the invariant theory of the Bezoutiant

Jaydeep V. Chipalkatti
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Abstract

We study the classical invariant theory of the Bezoutiant R(A,B) of a pair of binary forms A,B. It is shown that R(A,B) admits a Taylor expansion whose coefficients are (essentially) the odd transvectants (A,B)_{2r+1}. Moreover, R(A,B) is entirely determined by the first two terms M = (A,B)_1, N =(A,B)_3. Using the Plucker relations, we give equivariant formulae which express the higher transvectants (A,B)_5, (A,B)_7 in terms of M,N. We also describe a `reduction formula' which calculates B from the knowledge of A and R(A,B).

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Jaydeep V. Chipalkatti. 2004-06-21. On the invariant theory of the Bezoutiant. https://arxiv.org/abs/math/0406410

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