Let P(z) be a polynomial of degree n having all its zeros in |z|≤ k. For k = 1, it is known that for each r 〉 0 and |a|≥1,n(|a|-1){∫0^2π|P(e^iθ)|^rdθ}^1/r≤{∫0^2π|1+e^iθ|^rdθ}^1/rmax|z|=1...Let P(z) be a polynomial of degree n having all its zeros in |z|≤ k. For k = 1, it is known that for each r 〉 0 and |a|≥1,n(|a|-1){∫0^2π|P(e^iθ)|^rdθ}^1/r≤{∫0^2π|1+e^iθ|^rdθ}^1/rmax|z|=1|DzP(z)|.In this paper, we shall first consider the case when k≥1 and present certain generaliza- tions of this inequality. Also for k≤ 1, we shall prove an interesting result for Lacunary type of polynomials from which many results can be easily deduced.展开更多
In this paper we consider a class of polynomials P(z)=a0+∑v^n=tavZv, t≥ 1, not vanishing in |z| 〈k, k≥1 and investigate the dependence of max|z|=1 |P(Rz) -P(rz)] on max|z|=1|P(z)|, where 1≤ r 〈...In this paper we consider a class of polynomials P(z)=a0+∑v^n=tavZv, t≥ 1, not vanishing in |z| 〈k, k≥1 and investigate the dependence of max|z|=1 |P(Rz) -P(rz)] on max|z|=1|P(z)|, where 1≤ r 〈 R. Our result generalizes and refines some known polynomial inequalities.展开更多
基金supported by UGC under major research project scheme vide No. MRP-MAJOR-MATH-2013-29143
文摘Let P(z) be a polynomial of degree n having all its zeros in |z|≤ k. For k = 1, it is known that for each r 〉 0 and |a|≥1,n(|a|-1){∫0^2π|P(e^iθ)|^rdθ}^1/r≤{∫0^2π|1+e^iθ|^rdθ}^1/rmax|z|=1|DzP(z)|.In this paper, we shall first consider the case when k≥1 and present certain generaliza- tions of this inequality. Also for k≤ 1, we shall prove an interesting result for Lacunary type of polynomials from which many results can be easily deduced.
文摘In this paper we consider a class of polynomials P(z)=a0+∑v^n=tavZv, t≥ 1, not vanishing in |z| 〈k, k≥1 and investigate the dependence of max|z|=1 |P(Rz) -P(rz)] on max|z|=1|P(z)|, where 1≤ r 〈 R. Our result generalizes and refines some known polynomial inequalities.