Korean Journal of Mathematics

  • 제31권3호
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  • Pages.243-258
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  • 2023
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  • 1976-8605(pISSN)
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  • 2288-1433(eISSN)
강원경기수학회 (The Kangwon-Kyungki Mathematical Society)
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SUFFICIENT CONDITIONS FOR STARLIKENESS OF RECIPROCAL ORDER

  • 투고 : 2023.07.19
  • 심사 : 2023.08.30
  • 발행 : 2023.09.30
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초록

A normalized analytic function f defined on the unit disk 𝔻 is starlike of reciprocal order α, 0 ≤ α < 1, if Re(f(z)/(zf'(z))) > α for all z ∈ 𝔻. Such functions are starlike and therefore univalent in 𝔻. Using the well-known Miller-Mocanu differential subordination theory, sufficient conditions involving differential inclusions are obtained for a normalized analytic function to be starlike of reciprocal order α. Furthermore, a few conditions are derived for a function f to belong to a subclass of reciprocal starlike functions, satisfying |f(z)/(zf'(z)) - 1| < 1 - α.

키워드

과제정보

This work is supported by the institute fellowship from NIT Tiruchirappalli.

참고문헌

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