Annals of Communications in Mathematics

AbstractWe establish the generalized Hyers-Ulam stability of the 4 variable quadratic functional equation in Fuzzy Normed Spaces using two different methods.

AbstractIn this work, we investigate the Hyers-Ulam stability by using direct and fixed point methods for the quartic functional equation for positive integer p ≥ 3.

AbstractIn this paper, we investigate some stability results of the following finite dimensional additive functional equation where n is the positive integer with N − {0, 1, 2} and k is the only odd positive integers, in Fuzzy Normed space using direct and fixed point approaches.

ABSTRACT.In this paper, we determine some stability results concerning the quartic functional equation as of the form\[\sum_{b=1}^{s} \phi\!\left(-v_b + \sum_{a=1,\,a\ne b}^{s} v_a\right)- 4 \sum_{1 \le a < b < c \le s} \phi(v_a + v_b + v_c)- \sum_{b=1}^{s} \phi(2v_b)\]\[= (-4s+14)\sum_{a=1,\,a\ne b}^{s} \phi(v_a + v_b)+ (s-8)\phi\!\left(\sum_{a=1}^{s} v_a\right)\]\[\quad + 2 \left[\sum_{a=1,\,a\ne b}^{s} \phi(v_a - v_b)+ (s^{2}-7s+7)\sum_{a=1}^{s} \phi(v_a)\right],\]where any positive integers \( s \ge 3 \), in Banach algebra via direct and fixed point approaches.

AbstractIn this work, authors investigate the generalized Hyers-Ulam stability of the 4-variable quadratic functional equation of the form

AbstractWe examine the Ulam-Hyers stability of finite variable additive functional equation in fuzzy normed space using classical methods.