A note on sharpening of Erdos-Lax and Turan-type inequalities for a constrained polynomial

Document Type : Research Paper


Department of Mathematics, University of Kashmir, Srinagar-190006, India


The well-known Erdos-Lax and Turan-type inequalities, which relate the uniform norm of a univariate complex coefficient polynomial to its derivative on the unit circle in the plane, are discussed in this paper. We create some new inequalities here when there is a restriction on its zeros. The obtained results strengthen some recently proved Erdos-Lax and Turan-type inequalities for constrained polynomials and also produce various inequalities that are sharper than the previous ones known in a very rich literature on this subject.


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Volume 13, Issue 2
July 2022
Pages 3239-3249
  • Receive Date: 06 May 2022
  • Revise Date: 29 July 2022
  • Accept Date: 02 August 2022