Subclasses of λ-bi-pseudo-starlike functions with respect to symmetric points based on shell-like curves

• Autores: H. Ö. Güney, Gangadharan Murugusundaramoorthy, K. Vijaya
• Localización: Cubo: A Mathematical Journal, ISSN 0716-7776, ISSN-e 0719-0646, Vol. 23, Nº. 2, 2021, págs. 299-312
• Idioma: inglés
• DOI: 10.4067/S0719-06462021000200299
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• Resumen
  • español

    RESUMEN En este artículo definimos la subclase 𝒫𝒮ℒλ 8, Σ(α,ࣤp(z)) de la clase Σ de funciones bi-univalentes definidas en el disco unitario, llamadas λ -bi-pseudo-estrelladas, con respecto a puntos simétricos, relacionadas a curvas espirales en conexión con números de Fibonacci. Determinamos los coeficientes iniciales de Taylor-Maclaurin |a2| y |a3| para funciones f ∈ 𝒫𝒮ℒλ 8, Σ(α,ࣤp(z)). Más aíun determinamos el resultado de Fekete-Szegö para la clase de funciones ∈ 𝒫𝒮ℒλ 8, Σ(α,ࣤp(z)) y para los casos especiales α = 0, α = 1 y τ = -0:618 enunciamos corolarios mejorando los coeficientes iniciales de Taylor-Maclaurin |a2| y |a3|.

  • English

    ABSTRACT In this paper we de_ne the subclass 𝒫𝒮ℒλ 8, Σ(α,ࣤp(z)) of the class Σ of bi-univalent functions defined in the unit disk, called λ-bi-pseudo-starlike, with respect to symmetric points, related to shell-like curves connected with Fibonacci numbers. We determine the initial Taylor-Maclaurin coefficients |a2| and |a3| for functions f ∈ 𝒫𝒮ℒλ 8, Σ(α,ࣤp(z)). Further we determine the Fekete-Szegö result for the function class 𝒫𝒮ℒλ 8, Σ(α,ࣤp(z)) and for the special cases α = 0, α = 1 and τ = -0:618 we state corollaries improving the initial Taylor-Maclaurin coefficients |a2| and |a3|

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