ABSTRACT
In this paper, the sharp solutions of Fekete-Szegö problems are provided for class of quasi-convex mappings f1 of type B and class of quasi-convex mappings f2 of type B and order α defined on the unit ball in a complex Banach space, respectively, where x = 0 is a zero of order k + 1 of fi(x) − x (i = 1, 2). Compare with some recent works, our main theorems hold without additional restrictive conditions. Also, the proof of our main theorems are more simple than those given in the previous results.
Funding statement: This work was supported by the National Natural Science Foundation of China (No.12061035), Jiangxi Provincial Natural Science Foundation (No.20212BAB201012), Research Foundation of Jiangxi Provincial Department of Education of China (No.GJJ201104) and Research Foundation of Jiangxi Science and Technology Normal University (No. 2021QNBJRC003).
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