INTUITIONISTIC FUZZY STABILITY OF AN EULER-LAGRANGE TYPE QUARTIC FUNCTIONAL EQUATION

In this paper, we investigate the Hyers-Ulam stability of the following Euler-Lagrange type quartic functional equation <p class="disp_formula">$\begin{array}{*{20}{c}}{f(ax+y)+f(x+ay)+\frac{1}{2}a(a-1)^{2}f(x-y)}\\{=(a^{2}-1)^{2}(f(x)+f(y))+\frac{1}{2}a(a+1)^{2}f(x+y)}\end{array}$ in intuitionistic fuzzy normed spaces, where $a\neq 0, a\neq\pm1$. Furthermore, we investigate intuitionistic fuzzy continuity through the existence of a certain solution of a fuzzy stability problem for approximately Euler-Lagrange quartic functional equation.