{"title":"具有规定极点和限制零点的有理函数的增长估计","authors":"Ishfaq Dar, N. A. Rather, Mohd Shafi Wani","doi":"10.22075/IJNAA.2021.23465.2544","DOIUrl":null,"url":null,"abstract":"Let $r(z)= f(z)/w(z)$ where $f(z)$ be a polynomial of degree at most $n$ and $w(z)= prod_{j=1}^{n}(z-a_{j})$, $|a_j|> 1$ for $1leq j leq n.$ If the rational function $r(z)neq 0$ in $|z|< k$, then for $k =1$, it is known that $$left|r(Rz)right|leq left(frac{left|B(Rz)right|+1}{2}right) underset{|z|=1}sup|r(z)|,,, for ,,,|z|=1$$ where $ B(z)= prod_{j=1}^{n}left{(1-bar{a_{j}}z)/(z-a_{j})right}$. In this paper, we consider the case $k geq 1$ and obtain certain results concerning the growth of the maximum modulus of the rational functions with prescribed poles and restricted zeros in the Chebyshev norm on the unit circle in the complex plane.","PeriodicalId":14240,"journal":{"name":"International Journal of Nonlinear Analysis and Applications","volume":"13 1","pages":"247-252"},"PeriodicalIF":0.0000,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Growth estimate for rational functions with prescribed poles and restricted zeros\",\"authors\":\"Ishfaq Dar, N. A. Rather, Mohd Shafi Wani\",\"doi\":\"10.22075/IJNAA.2021.23465.2544\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Let $r(z)= f(z)/w(z)$ where $f(z)$ be a polynomial of degree at most $n$ and $w(z)= prod_{j=1}^{n}(z-a_{j})$, $|a_j|> 1$ for $1leq j leq n.$ If the rational function $r(z)neq 0$ in $|z|< k$, then for $k =1$, it is known that $$left|r(Rz)right|leq left(frac{left|B(Rz)right|+1}{2}right) underset{|z|=1}sup|r(z)|,,, for ,,,|z|=1$$ where $ B(z)= prod_{j=1}^{n}left{(1-bar{a_{j}}z)/(z-a_{j})right}$. In this paper, we consider the case $k geq 1$ and obtain certain results concerning the growth of the maximum modulus of the rational functions with prescribed poles and restricted zeros in the Chebyshev norm on the unit circle in the complex plane.\",\"PeriodicalId\":14240,\"journal\":{\"name\":\"International Journal of Nonlinear Analysis and Applications\",\"volume\":\"13 1\",\"pages\":\"247-252\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2022-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"International Journal of Nonlinear Analysis and Applications\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.22075/IJNAA.2021.23465.2544\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"Mathematics\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Nonlinear Analysis and Applications","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.22075/IJNAA.2021.23465.2544","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"Mathematics","Score":null,"Total":0}
引用次数: 0
摘要
让$ r (z) = f (z) / w (z), f (z)美元是美元最多$ n次多项式和w美元(z) = prod_ {j = 1} ^ {n} (z-a_ {j})美元,美元| a_j | > 1美元1 leq j leq n。如果美元有理函数r (z) neq 0美元在z $ | | < k美元,那么对于k = 1美元,众所周知,$ $ | r (Rz)左右| leq左(压裂{左| B (Rz)右| + 1}{2})支撑{| | z = 1}一口r (z) |……| | | z = 1 $ $ $ B (z) = prod_ {j = 1} ^ {n}左{(1块{现代{j}} z) / (z-a_ {j})右}$。本文考虑了复平面上单位圆上具有规定极点和限制零的有理函数在切比雪夫范数上的最大模的增长问题,得到了一些结果。
Growth estimate for rational functions with prescribed poles and restricted zeros
Let $r(z)= f(z)/w(z)$ where $f(z)$ be a polynomial of degree at most $n$ and $w(z)= prod_{j=1}^{n}(z-a_{j})$, $|a_j|> 1$ for $1leq j leq n.$ If the rational function $r(z)neq 0$ in $|z|< k$, then for $k =1$, it is known that $$left|r(Rz)right|leq left(frac{left|B(Rz)right|+1}{2}right) underset{|z|=1}sup|r(z)|,,, for ,,,|z|=1$$ where $ B(z)= prod_{j=1}^{n}left{(1-bar{a_{j}}z)/(z-a_{j})right}$. In this paper, we consider the case $k geq 1$ and obtain certain results concerning the growth of the maximum modulus of the rational functions with prescribed poles and restricted zeros in the Chebyshev norm on the unit circle in the complex plane.