REFINEMENTOFSOMEGENERALIZEDPOLYNOMIAL INEQUALITIES
DOI:
https://doi.org/10.56827/SEAJMMS.2023.1902.08Keywords:
Polynomials;Derivatives;PolarDerivative; Inequalities;MaximumModulus;Zeros.Abstract
Letp(z)beapolynomial of degreen,withp(z)= n ν=0 aνzν. Inthis paper,firstly,weprovearesultforboundsintwodifferentradii forthemaximum modulusof lacunarytypeofpolynomialshavingall zerosoutsideadiskofgiven radius. Next,we establisha result concerning themaximummodulus of polar derivativeof polynomial havingall zeros insideadiskout ofwhichsomefixed numberof zerosarecentredatorigin. Inparticularcasethis result reduces into ordinaryderivative.Ourresultsnotonlyproviderefinementsofearlierprovedresultsbutalsoopennewavenuesforotherresultsinthesamefieldofresearch.