• Title, Summary, Keyword: subordination chain

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Integral operators that preserve the subordination

  • Bulboaca, Teodor
    • Bulletin of the Korean Mathematical Society
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    • v.34 no.4
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    • pp.627-636
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    • 1997
  • Let $H(U)$ be the space of all analytic functions in the unit disk $U$ and let $K \subset H(U)$. For the operator $A_{\beta,\gamma} : K \longrightarrow H(U)$ defined by $$ A_{\beta,\gamma}(f)(z) = [\frac{z^\gamma}{\beta + \gamma} \int_{0}^{z} f^\beta (t)t^{\gamma-1} dt]^{1/\beta} $$ and $\beta,\gamma \in C$, we determined conditions on g(z), $\beta and \gamma$ such that $$ z[\frac{z}{f(z)]^\beta \prec z[\frac{z}{g(z)]^\beta implies z[\frac{z}{A_{\beta,\gamma}(f)(z)]^\beta \prec z[\frac{z}{A_{\beta,\gamma}(g)(z)]^\beta $$ and we presented some particular cases of our main result.

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DIFFERENTIAL SUBORDINATIONS AND SUPERORDINATIONS FOR GENERALIZED BESSEL FUNCTIONS

  • Al-Kharsani, Huda A.;Baricz, Arpad;Nisar, Kottakkaran S.
    • Bulletin of the Korean Mathematical Society
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    • v.53 no.1
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    • pp.127-138
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    • 2016
  • Differential subordination and superordination preserving properties for univalent functions in the open unit disk with an operator involving generalized Bessel functions are derived. Some particular cases involving trigonometric functions of our main results are also pointed out.