Geodesic
On a Class of Hyperbolic Polynomials
Matematičeskie zametki, Tome 83 (2008) no. 6, pp. 825-830.

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In the present paper, we investigate whether the roots of a biquadratic equation determined by a pair of real symmetric positive definite matrices of order 3 and a three-dimensional vector of parameters are real. We obtain the explicit representation of the discriminant of such a polynomial as the sum of at most two squares.
Keywords: biquadratic equation, real roots, hyperbolic polynomial, biquadratic form, skew-symmetric matrix.
Mots-clés : trace of a matrix 
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N. A. Zhura. On a Class of Hyperbolic Polynomials. Matematičeskie zametki, Tome 83 (2008) no. 6, pp. 825-830. http://geodesic.mathdoc.fr/item/MZM_2008_83_6_a2/

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