Aktu?lu and Gezer [1] introduced the concepts of lacunary equistatistical
convergence, lacunary statistical pointwise convergence and lacunary
statistical uniform convergence for sequences of functions. Recently, Kaya
and G?n?l [11] proved some analogs of the Korovkin approximation theorem via
lacunary equistatistical convergence by using test functions 1, x/1+x, y/1+y,
(x/1+x)2 +(y/1+y)2. We apply the notion of lacunary equistatistical
convergence to prove a Korovkin type approximation theorem for functions of
two variables by using test functions 1, x/1?x, y/1?y, (x/1?x)2+(y/1?y)2.
Basic Trigonometric Korovkin Approximation for Fuzzy Valued Functions of Two Variables
