“…for all x, y, t ∈ N. The equations (1.2) and (1.3) are applied to remove noise in an image by filtering techniques. The study of stability of several functional equations in various spaces and their solutions as rational functions can be found in [2], [3], [4], [5], [6], [7], [12], [15], [16], [17], [21], [22], [26], [27], [28].…”