Citation: | Jinyu Xia, Qi Liu, Yin Zhou, Zhiyong Rao, John Michael Rassias. SOME STUDIES ON EULER-LAGRANGE QUARTIC FUNCTIONAL EQUATIONS IN β-NORMED SPACES[J]. Journal of Applied Analysis & Computation, 2025, 15(3): 1770-1785. doi: 10.11948/20240405 |
In this paper, we study two types of Euler-Lagrange functional equations that map $ \jmath $ from normed spaces to $ \beta $-normed spaces using quartic functional equations. We will investigate the inequality under various transformations and perturbations using both fixed point and direct methods, to establish the Hyers-Ulam stability of quartic Euler-Lagrange functional equations.
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