Polynomials least deviating from zero in $L^p(-1;1) $, $ 0 \le p \le \infty $,  with a constraint on the location of
    
    
  
  
  
      
      
      
        
Ural mathematical journal, Tome 9 (2023) no. 2, pp. 157-164
    
  
  
  
  
  
    
      
      
        
      
      
      
    Voir la notice de l'article provenant de la source Math-Net.Ru
            
              			We study Chebyshev's problem on polynomials that deviate least from zero with respect to $L^p$-means on the interval $[-1;1]$ with a constraint on the location of roots of polynomials. More precisely, we consider the problem on the set $\mathcal{P}_n(D_R)$ of polynomials of degree $n$ that have unit leading coefficient and do not vanish in an open disk of radius $R \ge 1$. An exact solution is obtained for the geometric mean (for $p=0$) for all $R \ge 1$; and for $0$ for all $R \ge 1$ in the case of polynomials of even degree. For $0$ and $R\ge 1$, we obtain two-sided estimates of the value of the least deviation.
			
            
            
            
          
        
      
                  
                    
                    
                    
                        
Keywords: 
Algebraic polynomials, Chebyshev polynomials, сonstraints on the roots of a polynomial.
                    
                    
                    
                  
                
                
                @article{UMJ_2023_9_2_a12,
     author = {Alena E. Rokina},
     title = {Polynomials least deviating from zero in $L^p(-1;1) $, $ 0 \le p \le \infty $,  with a constraint on the location of},
     journal = {Ural mathematical journal},
     pages = {157--164},
     publisher = {mathdoc},
     volume = {9},
     number = {2},
     year = {2023},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/UMJ_2023_9_2_a12/}
}
                      
                      
                    TY - JOUR AU - Alena E. Rokina TI - Polynomials least deviating from zero in $L^p(-1;1) $, $ 0 \le p \le \infty $, with a constraint on the location of JO - Ural mathematical journal PY - 2023 SP - 157 EP - 164 VL - 9 IS - 2 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/UMJ_2023_9_2_a12/ LA - en ID - UMJ_2023_9_2_a12 ER -
%0 Journal Article %A Alena E. Rokina %T Polynomials least deviating from zero in $L^p(-1;1) $, $ 0 \le p \le \infty $, with a constraint on the location of %J Ural mathematical journal %D 2023 %P 157-164 %V 9 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/UMJ_2023_9_2_a12/ %G en %F UMJ_2023_9_2_a12
Alena E. Rokina. Polynomials least deviating from zero in $L^p(-1;1) $, $ 0 \le p \le \infty $, with a constraint on the location of. Ural mathematical journal, Tome 9 (2023) no. 2, pp. 157-164. http://geodesic.mathdoc.fr/item/UMJ_2023_9_2_a12/