3-VARIABLE ADDITIVE ρ-FUNCTIONAL INEQUALITIES IN FUZZY NORMED SPACES

Abstract

In this paper, we introduce and investigate the following additive rho-functional in-equalities

N(f (x + y + z) - f (x) - f (y) - f (z), t)

>= N (rho (2f (x + y/2 + z) - f (x) - f (y) - 2f(z)) , t),

N (2f (x + y + z) - f (x) - f (y) - 2f (z), t)

>= N (rho (2f (x + y + z/2) - f (x) - f (y) - f (z)) , t),

N(f (x + y + z) - f(x) - f(y) - f (z), t)

>= N (rho(2f (x + y + z/2) - f (x) - f (y) - f (z)) , t)

in fuzzy normed spaces.

Furthermore, we prove the Hyers-Ulam stability of the above additive rho-functional inequalities in fuzzy Banach spaces.