Subdiscriminant of symmetric matrices are sums of squares
نویسنده
چکیده
In this Note we prove that the subdiscriminants of a symmetric matrix are sums of squares. This generalizes a result of [2] stating that the discriminant of a symmetric is a sum of squares and is inspired by its proof. A different, less explicit proof that the discriminant of a symmetric is a sum of squares also apear in [3]. As a consequence, we obtain an algebraic proof of the fact that all the roots of the characteristic polynomial of a symmetric matrix are real.
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تاریخ انتشار 2005