On the instability of solutions of the homogeneous boundary value problem of Riemann type for quasiharmonic functions in circular domains
    
    
  
  
  
      
      
      
        
Vestnik Ûžno-Uralʹskogo gosudarstvennogo universiteta. Seriâ, Matematika, mehanika, fizika, Tome 10 (2018) no. 3, pp. 52-58
    
  
  
  
  
  
    
      
      
        
      
      
      
    Voir la notice de l'article provenant de la source Math-Net.Ru
            
              			We consider the boundary value problem of Riemann type (the conjugation problem) in the classes of piecewise quasiharmonic functions. A homogeneous problem of a Riemann type problem in the classes of piecewise quasiharmonic functions of the second kind in circular domains is studied in details. In particular, in this case a clear solution method is developed for a homogeneous problem of Riemann type, the logical essence of which consists in reducing the solution of the homogeneous problem under consideration to a sequential solution of the common homogeneous Riemann problem for analytic functions and two second-order linear differential Euler equations. Moreover, instability of the solutions of the homogeneous problem is determined with respect to the change in the radius value of the considered circular domain, and a complete picture of its solvability for different values of the index of the problem and the radius of the circular domain is constructed. It is proved that the main reason for the instability of the solutions of a homogeneous problem of Riemann type in classes of piecewise quasiharmonic functions of the second kind in circular domains with respect to the change in the radius value of the considered circular domain is the fact that the number of linear independent analytic solutions of homogeneous differential Euler equations, to which the desired Riemann type problem is reduced, depends essentially on  the radius of the considered circular region. In this paper we use the methods of the theory of functions of a complex variable, the theory of integral equations, and the analytic theory of differential equations.
			
            
            
            
          
        
      
                  
                    
                    
                    
                    
                    
                      
Keywords: 
the boundary value problem of Riemann type, piecewise quasiharmonic function, differential equation of Euler, radius of a circular domain.
Mots-clés : circular domains
                    
                  
                
                
                Mots-clés : circular domains
@article{VYURM_2018_10_3_a5,
     author = {K. M. Rasulov and Sh. S. Khankishieva},
     title = {On the instability of solutions of the homogeneous boundary value problem of {Riemann} type for quasiharmonic functions in circular domains},
     journal = {Vestnik \^U\v{z}no-Uralʹskogo gosudarstvennogo universiteta. Seri\^a, Matematika, mehanika, fizika},
     pages = {52--58},
     publisher = {mathdoc},
     volume = {10},
     number = {3},
     year = {2018},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VYURM_2018_10_3_a5/}
}
                      
                      
                    TY - JOUR AU - K. M. Rasulov AU - Sh. S. Khankishieva TI - On the instability of solutions of the homogeneous boundary value problem of Riemann type for quasiharmonic functions in circular domains JO - Vestnik Ûžno-Uralʹskogo gosudarstvennogo universiteta. Seriâ, Matematika, mehanika, fizika PY - 2018 SP - 52 EP - 58 VL - 10 IS - 3 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/VYURM_2018_10_3_a5/ LA - ru ID - VYURM_2018_10_3_a5 ER -
%0 Journal Article %A K. M. Rasulov %A Sh. S. Khankishieva %T On the instability of solutions of the homogeneous boundary value problem of Riemann type for quasiharmonic functions in circular domains %J Vestnik Ûžno-Uralʹskogo gosudarstvennogo universiteta. Seriâ, Matematika, mehanika, fizika %D 2018 %P 52-58 %V 10 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/VYURM_2018_10_3_a5/ %G ru %F VYURM_2018_10_3_a5
K. M. Rasulov; Sh. S. Khankishieva. On the instability of solutions of the homogeneous boundary value problem of Riemann type for quasiharmonic functions in circular domains. Vestnik Ûžno-Uralʹskogo gosudarstvennogo universiteta. Seriâ, Matematika, mehanika, fizika, Tome 10 (2018) no. 3, pp. 52-58. http://geodesic.mathdoc.fr/item/VYURM_2018_10_3_a5/
