Abstract In this article we give two possible generalizations of the Hermite–Hadamard integral inequality for class twice differentiable functions, where convexity property target function is not assumed in advance. They represent a refinement case convex/concave functions with numerous applications.

In this paper, following standard arguments, the maximum Renyi entropy problem for the weighted case is analyzed. We verify that under some constrains on weight function, the Student-r and Student-t distributions maximize the weighted Renyi entropy. Furthermore, an extended version of the Hadamard inequality is derived.

In this paper, firstly we have established Hermite–Hadamard-Fejér inequality for fractional integrals. Secondly, an integral identity and some HermiteHadamard-Fejér type integral inequalities for the fractional integrals have been obtained. The some results presented here would provide extensions of those given in earlier works. Mathematics Subject Classification (2010): 26A51, 26A33, 26D10.