@ARTICLE{10.21494/ISTE.OP.2023.1000, TITLE={Remarques sur les surjections des groupes unitaires}, AUTHOR={Naseam Al-Kuleab, }, JOURNAL={Avancées en Mathématiques Pures et Appliquées}, VOLUME={14}, NUMBER={Numéro 4 (Septembre 2023)}, YEAR={2023}, URL={https://www.openscience.fr/Remarques-sur-les-surjections-des-groupes-unitaires}, DOI={10.21494/ISTE.OP.2023.1000}, ISSN={1869-6090}, ABSTRACT={The main purpose of this paper is to study unital ring homomorphisms of associative rings $$$\varphi : R\rightarrow S$$$ satisfying one of the following conditions : (a) the unit-preserving property : $$$\varphi(R^{\times})=S^{\times}$$$ and (b) the inverse unit-preserving property : $$$\varphi^{-1}(S^{\times})=R^{\times}$$$. We establish the relationship between these two conditions. Several characterizations of such conditions are settled. An application to the index of unit groups of rings $$$R\subset S$$$ having a nonzero common ideal is given.}}