Geodesic
On an Orthogonality Equation in Normed Spaces
Funkcionalʹnyj analiz i ego priloženiâ, Tome 52 (2018) no. 3, pp. 79-83.

Voir la notice de l'article provenant de la source Math-Net.Ru

The aim of this paper is to give an answer to the question, posed by Alsina, Sikorska, and Tomás, as to whether each norm derivative preserving mapping is necessarily linear.
Keywords: norm derivative, functional equation.
Mots-clés : quotient space 
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P. Wójcik. On an Orthogonality Equation in Normed Spaces. Funkcionalʹnyj analiz i ego priloženiâ, Tome 52 (2018) no. 3, pp. 79-83. http://geodesic.mathdoc.fr/item/FAA_2018_52_3_a6/

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