Nonlinear Functional Analysis and Applications

  • 제28권2호
  • /
  • Pages.421-437
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  • 2023
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  • 1229-1595(pISSN)
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  • 2466-0973(eISSN)
경남대학교 수학교육과 (Kyungnam University, Department of Mathematics Eduaction)
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IMPROVED BOUNDS OF POLYNOMIAL INEQUALITIES WITH RESTRICTED ZERO

  • Robinson Soraisam (Department of Mathematics, National Institute of Technology Manipur) ;
  • Nirmal Kumar Singha (Department of Mathematics, National Institute of Technology Manipur) ;
  • Barchand Chanam (Department of Mathematics, National Institute of Technology Manipur)
  • 투고 : 2022.08.10
  • 심사 : 2022.10.18
  • 발행 : 2023.06.15
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⟨ 이전 논문 다음 논문 ⟩

초록

Let p(z) be a polynomial of degree n having no zero in |z| < k, k ≥ 1. Then Malik [12] obtained the following inequality: $${_{max \atop {\mid}z{\mid}=1}{\mid}p{\prime}(z){\mid}{\leq}{\frac{n}{1+k}}{_{max \atop {\mid}z{\mid}=1}{\mid}p(z){\mid}.$$ In this paper, we shall first improve as well as generalize the above inequality. Further, we also improve the bounds of two known inequalities obtained by Govil et al. [8].

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과제정보

We are thankful to NIT, Manipur for providing us financial support. We are also grateful to the referee for his/her useful suggestions.

참고문헌

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