Intuitionistic Fuzzy Stability of Jensen-Type Quadratic Functional Equations


Zhihua Wang, Themistocles M. Rassias, Reza Saadati




In this paper, we prove some stability results for Jensen-type quadratic functional equations \[ 2f\left(\frac{x+y}2\right)+2f\left(\frac{x-y}2\right)=f(x)+f(y), \] \[ f(ax+ay)+f(ax-ay)=2a^2f(x)+2a^2f(y) \] in intuitionistic fuzzy normed spaces for a nonzero real number $a$ with $a\neq\pm\frac12$.