Communications of the Korean Mathematical Society (대한수학회논문집)

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SHARP COEFFICIENT INEQUALITIES FOR CERTAIN SUBCLASSES OF BI-UNIVALENT BAZILEVIČ FUNCTIONS

  • Received : 2020.12.16
  • Accepted : 2021.08.13
  • Published : 2022.01.31
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Abstract

In the present paper, we introduce the subclasses 𝔅1Σ(𝜇), B1Σ(𝜇, 𝛾) and UΣ(𝜇, 𝛾) of bi-univalent Bazilevič functions which are defined in the open unit disk 𝔻. Further, we obtain sharp estimates on initial coefficients a2, a3, a4 and also sharp estimate on the Fekete-Szegö functional a3 - ka22 for the functions belong to these subclasses.

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References

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