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arXiv · 1507.07899

Multivariate discriminant and iterated resultant

Jingjun Han
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Abstract

In this paper, we study the relationship between iterated resultant and multivariate discriminant. We show that, for generic form $f(X_n)$ with even degree $d$, if the polynomial is squarefreed after each iteration, the multivariate discriminant $Δ(f)$ is a factor of the squarefreed iterated resultant. In fact, we find a factor $Hp(f,[x_1,\ldots,x_n])$ of the squarefreed iterated resultant, and prove that the multivariate discriminant $Δ(f)$ is a factor of $Hp(f,[x_1,\ldots,x_n])$. Moreover, we conjecture that $Hp(f,[x_1,\ldots,x_n])=Δ(f)$ holds for generic form $f$, and show that it is true for generic trivariate form $f(x,y,z)$.

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Jingjun Han. 2016-05-14. Multivariate discriminant and iterated resultant. https://arxiv.org/abs/1507.07899

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