Mathematica Bohemica, Vol. 149, No. 1, pp. 49-55, 2024

The unit group of some fields of the form $\mathbb{Q}(\sqrt2, \sqrt{p}, \sqrt{q}, \sqrt{-l})$

Moha Ben Taleb El Hamam

Received June 3, 2022.   Published online February 9, 2023.

Abstract:  Let $p$ and $q$ be two different prime integers such that $p\equiv q\equiv3\pmod8$ with $(p/q)=1$, and $l$ a positive odd square-free integer relatively prime to $p$ and $q$. In this paper we investigate the unit groups of number fields $\mathbb L=\mathbb{Q}(\sqrt2, \sqrt{p}, \sqrt{q}, \sqrt{-l})$.
Keywords:  unit group; multiquadratic number fields; unit index
Classification MSC:  11R27, 11R04, 11R29

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Affiliations:   Moha Ben Taleb El Hamam, Sidi Mohamed Ben Abdellah University, Faculty of Sciences Dhar El Mahraz, Fez, Morocco, e-mail:

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