On the neighborhoods of certain subclasses of close-to-convex and quasi-convex

The neighborhoods of certain subclasses of close-to-convex and quasi-convex functions with respect to k-symmetric points are studied. If f is in \mathcal S_s,\ n^(k)A, B or \mathcal C_s,\ n^(k)A, B, some sufficient conditions are established such that all functions g\in\mathcal N_\delta(f) are included in \mathcal S_s,\ n^(k)A, B with this \delta being the best possibility. Some of the results, presented in this paper, generalize and extend the corresponding results existing in some literatures.