• 제목/요약/키워드: subordination

검색결과 192건 처리시간 0.02초

STARLIKENESS AND SCHWARZIAN DERIVATIVES OF HIGHER ORDER OF ANALYTIC FUNCTIONS

  • Kwon, Ohsang;Sim, Youngjae
    • 대한수학회논문집
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    • 제32권1호
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    • pp.93-106
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    • 2017
  • In this paper we apply the third-order differential subordination results to normalized analytic functions in the open unit disk. We obtain appropriate classes of admissible functions and find some sufficient conditions of functions to be starlike associated with Tamanoi's Schwarzian derivative of third order. Several interesting examples are also discussed.

COEFFICIENT ESTIMATES FOR A SUBCLASS OF ANALYTIC BI-UNIVALENT FUNCTIONS

  • Adegani, Ebrahim Analouei;Bulut, Serap;Zireh, Ahmad
    • 대한수학회보
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    • 제55권2호
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    • pp.405-413
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    • 2018
  • In this work, we use the Faber polynomial expansions to find upper bounds for the coefficients of analytic bi-univalent functions in subclass $\Sigma({\tau},{\gamma},{\varphi})$ which is defined by subordination conditions in the open unit disk ${\mathbb{U}}$. In certain cases, our estimates improve some of those existing coefficient bounds.

Differential Sandwich Theorem for Multivalent Meromorphic Functions associated with the Liu-Srivastava Operator

  • Ali, Rosihan M.;Chandrashekar, R.;Lee, See-Keong;Swaminathan, A.;Ravichandran, V.
    • Kyungpook Mathematical Journal
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    • 제51권2호
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    • pp.217-232
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    • 2011
  • Differential subordination and superordination results are obtained for multivalent meromorphic functions associated with the Liu-Srivastava linear operator in the punctured unit disk. These results are derived by investigating appropriate classes of admissible functions. Sandwich-type results are also obtained.

Sandwich Results for Certain Subclasses of Multivalent Analytic Functions Defined by Srivastava-Attiya Operator

  • Aouf, M.K.;Shamandy, A.;Mostafa, A.O.;Adwan, Eman A.
    • Kyungpook Mathematical Journal
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    • 제52권2호
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    • pp.209-222
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    • 2012
  • In this paper, we obtain some applications of first order differential subordination and superordination results involving the operator $J_{s,b}^{{\lambda},p}$ for certain normalized p-valent analytic functions associated with that operator.

On a Class of Meromorphic Functions Defined by Certain Linear Operators

  • Kumar, Shanmugam Sivaprasad;Taneja, Harish Chander
    • Kyungpook Mathematical Journal
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    • 제49권4호
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    • pp.631-646
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    • 2009
  • In the present investigation, we introduce new classes of p-valent meromorphic functions defined by Liu-Srivastava linear operator and the multiplier transform and study their properties by using certain first order differential subordination and superordination.

First Order Differential Subordinations for Carathéodory Functions

  • Gandhi, Shweta;Kumar, Sushil;Ravichandran, V.
    • Kyungpook Mathematical Journal
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    • 제58권2호
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    • pp.257-270
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    • 2018
  • The well-known theory of differential subordination developed by Miller and Mocanu is applied to obtain several inclusions between $Carath{\acute{e}}odory$ functions and starlike functions. These inclusions provide sufficient conditions for normalized analytic functions to belong to certain class of Ma-Minda starlike functions.

On Certain Class of Multivalent Functions Involving the Cho-Kwon-Srivastava Operator

  • Shenan, Jamal Mohammad
    • Kyungpook Mathematical Journal
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    • 제52권1호
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    • pp.21-32
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    • 2012
  • In this paper a new subclass of multivalent functions with negative coefficients defined by Cho-Kwon-Srivastava operator is introduced. Coefficient estimate and inclusion relationships involving the neighborhoods of p-valently analytic functions are investigated for this class. Further subordination result and results on partial sums for this class are also found.

ESTIMATE FOR INITIAL MACLAURIN COEFFICIENTS OF GENERAL SUBCLASSES OF BI-UNIVALENT FUNCTIONS OF COMPLEX ORDER INVOLVING SUBORDINATION

  • Altinkaya, Sahsene;Yalcin, Sibel
    • 호남수학학술지
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    • 제40권3호
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    • pp.391-400
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    • 2018
  • The object of this paper to construct a new class $$A^m_{{\mu},{\lambda},{\delta}}({\alpha},{\beta},{\gamma},t,{\Psi})$$ of bi-univalent functions of complex order defined in the open unit disc. The second and the third coefficients of the Taylor-Maclaurin series for functions in the new subclass are determined. Several special consequences of the results are also indicated.

ON A NEW CLASS OF SALAGEAN-TYPE HARMONIC UNIVALENT FUNCTIONS ASSOCIATED WITH SUBORDINATION

  • Altinkaya, Sahsene;Cakmak, Serkan;Yalcin, Sibel
    • 호남수학학술지
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    • 제40권3호
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    • pp.433-446
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    • 2018
  • In this present investigation, we introduce a new class of harmonic univalent functions of the form $f=h+{\bar{g}}$ in the open unit disk ${\Delta}$. We get basic properties, like, necessary and sufficient convolution conditions, distortion bounds, compactness and extreme points for these classes of functions.

On Applications of Differential Subordination to Certain Subclass of Multivalent Functions

  • Aghalary, Rasoul;Wang, Zhi-Gang
    • Kyungpook Mathematical Journal
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    • 제49권2호
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    • pp.265-281
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    • 2009
  • In the present paper, we introduce and investigate a new subclass of multivalent functions associated with the Cho-Kwon-Srivastava operator $\tau^{\lambda}_p(a,c)$. Such results as inclusion relationships, convolution properties and criteria for starlikeness are proved. Relevant connections of the results presented here with those obtained in earlier works are also pointed out.