Characterizations of pseudolinear and semistrictly quasilinear functions
DOI:
https://doi.org/10.24193/subbmath.2026.2.02Keywords:
pseudolinear functions, semistrictly quasilinear functions, nonsmooth analysis, conditions for pseudolinearity, semistrict quasilinearityAbstract
In this paper, we obtain several new complete characterizations of pseudolinear functions. Two of the results are of first-order and one is derivative free. The results are derived in terms of the Clarke-Rockafellar subdifferential. Additionally, we prove a characterization of the semistrictly quasilinear functions. It is similar to the derivative free characterization of the pseudolinear functions. We also find the conditions such that a semistrictly quasilinear function become pseudolinear.
Mathematics Subject Classification (2010): 26B25, 49J52.
Received 28 November 2025; Accepted 12 April 2026.
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