Analytical formula for the roots of the general complex cubic polynomial

Ibrahim Baydoun

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arXiv · 1512.07585

Analytical formula for the roots of the general complex cubic polynomial

Ibrahim Baydoun

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Abstract

We present a new method to calculate analytically the roots of the general complex polynomial of degree three. Thismethod is based on the approach of appropriated changes of variable involving an arbitrary parameter. The advantageof this method is to calculate the roots of the cubic polynomial as uniform formula using the standard convention of thesquare and cubic roots. In contrast, the reference methods for this problem, as Cardan-Tartaglia and Lagrange, give theroots of the cubic polynomial as expressions with case distinctions which are incorrect using the standar convention.

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Ibrahim Baydoun. 2015-12-21. Analytical formula for the roots of the general complex cubic polynomial. https://arxiv.org/abs/1512.07585

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