# Stability of a Quadratic-Reciprocal Functional Equation: Direct Method

## DOI:

https://doi.org/10.26713/cma.v14i5.2224## Keywords:

Quadratic reciprocal functional equation, Ulam-Hyers stability, Fuzzy Banach algebra## Abstract

In this paper, we establish the Hyers-Ulam, Hyers-Ulam-Rassias, generalized Hyers-Ulam-Rassias, and Rassias stability results of the quadratic-reciprocal functional equation:

\begin{align*}

f(x+y)=\frac{f(x)f(y)}{f(x)+f(y)+2\sqrt{f(x)f(y)}}

\end{align*}

connected with fuzzy homomorphisms and fuzzy derivations between fuzzy Banach algebras using direct method.

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*Communications in Mathematics and Applications*,

*14*(5), 1615–1624. https://doi.org/10.26713/cma.v14i5.2224

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