Better approximations for quasi-convex functions

In this paper, by using Hölder-Işcan, Hölder integral inequality and an general identity for diérentiable functions we can get new estimates on generalization of Hadamard, Ostrowski and Simpson type integral inequalities for functions whose derivatives in absolute value at certain power are quasi-convex functions. It is proved that the result obtained Hölder-Işcan integral inequality is better than the result obtained Hölder inequality.