Coefficient estimates in new subclasses of analytic and bi-univalent functions defined by the combinations of the $q$-derivative and the Sǎlǎgean derivative operator
Abstract
UDC 517.53 We introduce and study two new subclasses of the function class $\Sigma $ of bi-univalent functions defined in the open unit disk and associated with the Sǎlǎgean and $q$-derivative operators. Furthermore, we find estimates for the Taylor–Maclaurin coefficients $|a_{2}|$ and $|a_{3}|$ of the functions from these new subclasses. The accumulated results are quite interesting and new.
Fields of Study & Subjects
Analytic and geometric function theory
Approximation Theory and Sequence Spaces
Mathematical functions and polynomials
Publication details
- Journal / source
- Ukrains’kyi Matematychnyi Zhurnal
- Publisher
- SIGMA (Symmetry, Integrability and Geometry: Methods and Application)
- Volume
- 78
- Issue
- 1-2
- Pages
- 88–88
- Publication date
- 27 January 2026