Abstract
Characterizations of pairs of functions that can be separated by a strongly convex, approximately concave or c-quadratic-affine function are presented. As consequences, stability results of the Hyers-Ulam type are obtained.
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Dedicated to Professor Roman Ger on his 70th birthday
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Merentes, N., Nikodem, K. Strong convexity and separation theorems. Aequat. Math. 90, 47–55 (2016). https://doi.org/10.1007/s00010-015-0360-4
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DOI: https://doi.org/10.1007/s00010-015-0360-4