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arXiv · 0909.4865

On the typical rank of real binary forms

Pierre Comon·Giorgio Ottaviani
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Abstract

We determine the rank of a general real binary form of degree d=4 and d=5. In the case d=5, the possible values of the rank of such general forms are 3,4,5. The existence of three typical ranks was unexpected. We prove that a real binary form of degree d with d real roots has rank d.

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Pierre Comon, Giorgio Ottaviani. 2009-09-26. On the typical rank of real binary forms. https://arxiv.org/abs/0909.4865

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