Joubert’s Theorem Fails in Characteristic 2

نویسنده

  • ZINOVY REICHSTEIN
چکیده

Let L/K be a separable field extension of degree 6. An 1867 theorem of P. Joubert asserts that if char(K) 6= 2 then L is generated over K by an element whose minimal polynomial is of the form t + at + bt + ct+ d for some a, b, c, d ∈ K. We show that this theorem fails in

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تاریخ انتشار 2014