Stud. Univ. Babe¸s-Bolyai Math. 68(2023), No. 2, 279–293 DOI: 10.24193/subbmath.2023.2.05 Certain sufficient conditions for φ- like functions in a parabolic region Hardeep Kaur, Richa Brar and Sukhwinder Singh Billing Abstract. To obtain the main result of the present paper we use the technique of differential subordination. As special cases of our main result, we obtain sufficient conditions for f ∈A to be φ-like, starlike and close-to-convex in a parabolic region. Mathematics Subject Classification (2010): 30C80, 30C45. Keywords: Analytic function, differential subordination, parabolic φ-like func- tion, parabolic starlike function, close-to-convex function. 1. Introduction Let us denote the class of analytic functions in the unit disk E = {z ∈ C : |z| < 1} by H. For a ∈ C and n ∈ N, let H[a, n] be the subclass of H consisting of the functions of the form f (z)= a + a n z n + a n+1 z n+1 + .... Let A be the class of functions f , analytic in the unit disk E and normalized by the conditions f (0) = f 0 (0) - 1 = 0. Let S denote the class of all analytic univalent functions f defined in the open unit disk E which are normalized by the conditions f (0) = f 0 (0) - 1 = 0. The Taylor series expansion of any function f ∈S is f (z)= z + a 2 z 2 + a 3 z 3 + .... Let the functions f and g be analytic in E. We say that f is subordinate to g written as f ≺ g in E, if there exists a Schwarz function φ in E (i.e. φ is regular in |z| < 1, Received 21 May 2020; Accepted 21 July 2020. Studia UBB MATHEMATICA. Published by Babe¸s-Bolyai University This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.