In this paper, we investigate the Hyers-Ulam stability of additive and Fréchet functional equations on restricted domains. We improve the bounds and thus the results obtained by S. M. Jung and J. M. Rassias. As a consequence, we obtain asymptotic behaviors of functional equations of different types. One of the objectives of this paper is to bring out the involvement of functional equations in various characterizations of inner product spaces.
Citation: Choonkil Park, Abbas Najati, Batool Noori, Mohammad B. Moghimi. Additive and Fréchet functional equations on restricted domains with some characterizations of inner product spaces[J]. AIMS Mathematics, 2022, 7(3): 3379-3394. doi: 10.3934/math.2022188
In this paper, we investigate the Hyers-Ulam stability of additive and Fréchet functional equations on restricted domains. We improve the bounds and thus the results obtained by S. M. Jung and J. M. Rassias. As a consequence, we obtain asymptotic behaviors of functional equations of different types. One of the objectives of this paper is to bring out the involvement of functional equations in various characterizations of inner product spaces.
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