• 제목/요약/키워드: convex and starlike functions

검색결과 103건 처리시간 0.03초

ON A CLASS OF QUANTUM ALPHA-CONVEX FUNCTIONS

  • NOOR, KHALIDA INAYAT;BADAR, RIZWAN S.
    • Journal of applied mathematics & informatics
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    • 제36권5_6호
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    • pp.567-574
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    • 2018
  • Let $f:f(z)=z+{\sum^{{\infty}}_{n=2}}a_nz^n$ be analytic in the open unit disc E. Then f is said to belong to the class $M_{\alpha}$ of alpha-convex functions, if it satisfies the condition ${\Re}\{(1-{{\alpha})}{\frac{zf^{\prime}(z)}{f(z)}}+{{\alpha}}{\frac{(zf^{\prime}(z))^{\prime})}{f^{\prime}(z)}}\}$ > 0, ($z{\in}E$). In this paper, we introduce and study q-analogue of the class $M_{\alpha}$ by using concepts of Quantum Analysis. It is shown that the functions in this new class $M(q,{\alpha})$ are q-starlike. A problem related to q-Bernardi operator is also investigated.

GENERALIZED CLOSE-TO-CONVEX FUNCTIONS

  • NOOR, KHALIDA INAYAT
    • 호남수학학술지
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    • 제17권1호
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    • pp.97-106
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    • 1995
  • We introduce a new class of analytic functions in the unit disk which generalizes the concepts of close-to-convexity and of bounded boundary rotation, and study its various properties including its connection with other classes of analytic and univalent functions.

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SUBORDINATION ON δ-CONVEX FUNCTIONS IN A SECTOR

  • MARJONO, MARJONO;THOMAS, D.K.
    • 호남수학학술지
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    • 제23권1호
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    • pp.41-50
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    • 2001
  • This paper concerns with the subclass of normalized analytic function f in D = {z : |z| < 1}, namely a ${\delta}$-convex function in a sector. This subclass is denoted by ${\Delta}({\delta})$, where ${\delta}$ is a real positive. Given $0<{\beta}{\leq}1$ then for $z{\in}D$, the exact ${\alpha}({\beta},\;{\delta})$ is found such that $f{\in}{\Delta}({\delta})$ implies $f{\in}S^*({\beta})$, where $S^*({\beta})$ is starlike of order ${\beta}$ in a sector. This work is a more general version of the result of Nunokawa and Thomas [11].

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CERTAIN PROPERTIES OF A NEW SUBCLASS OF ANALYTIC AND p-VALENTLY CLOSE-TO-CONVEX FUNCTIONS

  • BULUT, Serap
    • 호남수학학술지
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    • 제39권2호
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    • pp.233-245
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    • 2017
  • In the present paper we introduce and investigate an interesting subclass ${\mathcal{K}}^{(k)}_s({\gamma},p) $ of analytic and p-valently close-to-convex functions in the open unit disk ${\mathbb{U}}$. For functions belonging to this class, we derive several properties as the inclusion relationships and distortion theorems. The various results presented here would generalize many known recent results.

Certain Subclasses of k-uniformly Functions Involving the Generalized Fractional Differintegral Operator

  • Seoudy, Tamer Mohamed
    • Kyungpook Mathematical Journal
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    • 제58권2호
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    • pp.243-255
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    • 2018
  • We introduce several k-uniformly subclasses of p-valent functions defined by the generalized fractional differintegral operator and investigate various inclusion relationships for these subclasses. Some interesting applications involving certain classes of integral operators are also considered.

Multivalent Harmonic Uniformly Starlike Functions

  • Ahuja, Om;Joshi, Santosh;Sangle, Naveneet
    • Kyungpook Mathematical Journal
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    • 제49권3호
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    • pp.545-555
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    • 2009
  • In this paper, we investigate a generalized family of complex-valued harmonic functions that are multivalent, sense-preserving, and are associated with k-uniformly harmonic functions in the unit disk. The results obtained here include a number of known and new results as their special cases.

ON THE FEKETE-SZEGO PROBLEM FOR CERTAIN ANALYTIC FUNCTIONS

  • Kwon, Oh-Sang;Cho, Nak-Eun
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제10권4호
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    • pp.265-271
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    • 2003
  • Let $CS_\alpha(\beta)$ denote the class of normalized strongly $\alpha$-close-to-convex functions of order $\beta$, defined in the open unit disk $\cal{U}$ of $\mathbb{C}$${\mid}arg{(1-{\alpha})\frac{f(z)}{g(z)}+{\alpha}\frac{zf'(z)}{g(z)}}{\mid}\;\leq\frac{\pi}{2}{\beta}(\alpha,\beta\geq0)$ such that $g\; \in\;S^{\ask}$, the class of normalized starlike unctions. In this paper, we obtain the sharp Fekete-Szego inequalities for functions belonging to $CS_\alpha(\beta)$.

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