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A note on sharpening of Erdos-Lax and Turan-type inequalities for a constrained polynomial | ||
International Journal of Nonlinear Analysis and Applications | ||
مقاله 260، دوره 13، شماره 2، مهر 2022، صفحه 3239-3249 اصل مقاله (363.17 K) | ||
نوع مقاله: Research Paper | ||
شناسه دیجیتال (DOI): 10.22075/ijnaa.2022.27098.3498 | ||
نویسنده | ||
Adil Hussain Malik* | ||
Department of Mathematics, University of Kashmir, Srinagar-190006, India | ||
تاریخ دریافت: 16 اردیبهشت 1401، تاریخ بازنگری: 07 مرداد 1401، تاریخ پذیرش: 11 مرداد 1401 | ||
چکیده | ||
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. | ||
کلیدواژهها | ||
Complex domain؛ Rouche's theorem؛ Zeros | ||
مراجع | ||
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