Abstract
For \(-1\le B<A\le 1\), let \({\mathcal {S}}^*(A,B)\) denote the class of Janowski starlike functions that satisfy the subordination relation \(zf'(z)/f(z)\prec (1+Az)/(1+Bz)\). In the present article, we determine the sharp estimate of the pre-Schwarzian norm for the functions in the class \({\mathcal {S}}^*(A,B)\).
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Acknowledgements
The authors thank the referee for the constructive comments which helped to improve the presentation of the paper. The second named author thanks the University Grants Commission for the financial support through UGC Fellowship (Grant No. MAY2018-429303).
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Ali, M.F., Pal, S. Pre-Schwarzian norm estimates for the class of janowski starlike functions. Monatsh Math 201, 311–327 (2023). https://doi.org/10.1007/s00605-022-01756-4
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DOI: https://doi.org/10.1007/s00605-022-01756-4