q-Szász–Mirakyan–Kantorovich type operators preserving some test functions

In this paper, we introduce a q -analogue of the Szász–Mirakyan–Kantorovich operators and we propose two different modifications of the q -Szász–Mirakyan–Kantorovich operators. These modifications preserve some test functions. We also examine the rate of convergence for the constructed operators by means of modulus of continuity.