**AUTHORS:**Seong Sik Kim, John Michael Rassias, Soo Hwan Kim

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**ABSTRACT:**
In this paper, we present a fixed point results which was proved by Khamsi [9] in modular function
spaces to prove the generalized Hyers-Ulam stability of a nonic functional equation :
f(x + 5y) − 9f(x + 4y) + 36f(x + 3y) − 84f(x + 2y) + 126f(x + y) − 126f(x)
+ 84f(x − y) − 36f(x − 2y) + 9f(x − 3y) − f(x − 4y) = 9 ! f(y),
where 9 ! = 362880 in modular spaces

**KEYWORDS:**
- Generalized Hyers-Ulam-Rassias stability, Modular spaces, Nonic functional equations

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