Abstract
We prove that the kernels of Bernstein, Stancu and Kantorovich operators are proximinal sets, therefore the infimum of Hyers–Ulam constants is also a Hyers–Ulam constant for the above mentioned operators. Moreover, we investigate what happens when the supremum norm is replaced by the L 1-norm.
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Popa, D., Raşa, I. Best constant in stability of some positive linear operators. Aequat. Math. 90, 719–726 (2016). https://doi.org/10.1007/s00010-016-0405-3
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DOI: https://doi.org/10.1007/s00010-016-0405-3