On the stability of a \(k\)-cubic functional equation in intuitionistic fuzzy \(n\)-normed spaces (Q310872)

Let \(k\) be any real number. The functional equation \[ f(kx+y)+f(kx-y) = kf(x+y)+kf(x-y) + 2k(k^2 - 1) f(x) \] for all \(x, y \in \mathbb{R}\) is called the \(k\)-cubic functional equation. It is known that \(f(x) = x^3\) satisfies this equation. The authors prove some stability results concerning this functional equation in intuitionistic fuzzy \(n\)-normed spaces.