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Integral Inequalities for the Growth and Higher Derivative of Polynomials

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Abstract

Let \(P(z)\) be a polynomial of degree \(n\) which does not vanish in \(|z|<1\), it was proved by S. Gulzar [7] that

$$\left|\left|z^{s}P^{(s)}(z)+\beta\frac{n(n-1)...(n-s+1)}{2^{s}}P(z)\right|\right|_{p}\leqslant n(n-1)...(n-s+1)\left|\left|\left(1+\frac{\beta}{2^{s}}\right)z+\frac{\beta}{2^{s}}\right|\right|_{p}\frac{\left|\left|P(z)\right|\right|_{p}}{\left|\left|1+z\right|\right|_{p}}$$

for every \(\beta\in\mathbb{C}\) with \(|\beta|\leqslant 1\), \(1\leqslant s\leqslant n\) and \(0\leqslant p<\infty\). In this paper we extend the above result to the growth of polynomials and also generalize the above and other related results in this direction.

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Correspondence to N. A. Rather, A. Bhat or M. Shafi.

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Rather, N.A., Bhat, A. & Shafi, M. Integral Inequalities for the Growth and Higher Derivative of Polynomials. J. Contemp. Mathemat. Anal. 57, 242–251 (2022). https://doi.org/10.3103/S1068362322040021

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  • DOI: https://doi.org/10.3103/S1068362322040021

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