# On approximation of approximately quadratic mappings by quadratic mappings

### Abstract

In this paper we establish an approximation of approximately quadratic mappings by quadratic mappings, which solves the pertinent Ulam stability problem.

### Keywords

Ulam problem; Ulam type problem; general Ulam problem; quadratic mapping; approximately quadratic mapping; approximation; Ulam stability problem; normed linear space; complete normed linear space

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*Annales Mathematicae Silesianae*,

*15*, 67-78. Retrieved from https://journals.us.edu.pl/index.php/AMSIL/article/view/14116

Pedagogical Department E. E., Section of Mathematics and Informatics, National and Capodistrian University of Athens. Grece Greece

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