Comments on fixed point results in classes of function with values in a b–metric space

Abstract We prove and discuss several fixed point results for nonlinear operators, acting on some classes of functions with values in a b-metric space. Thus we generalize extend recent theorem Dung Hang (J Math Anal Appl 462:131–147, 2018), motivated by outcomes Ulam type stability. As simple consequence obtain, particular, that approximate (in sense) eigenvalues linear function spaces, must be while eigenvectors are close to the same eigenvalue. Our also provide natural generalizations extensions classical Banach Contraction Principle.