Approximation by $$\vartheta $$-Baskakov–Durrmeyer-Type Hybrid Operators

In this work, we present a Durrmeyer-type operator having the basis functions in summation and integration due to Aral (Math Commun 24:119–131, 2019) and Pǎltǎnea (Carpath J Math 24(3):378–385, 2008) that preserve the constant functions. We compute the rate of convergence of these operators in a weighted space and also computed a quantitative Voronovskaja-type asymptotic formula as well as a Gruss-Voronovskaya-type approximation.