On a class of hyperbolic equations with third-order integrals
    
    
  
  
  
      
      
      
        
Ufa mathematical journal, Tome 15 (2023) no. 2, pp. 20-30
    
  
  
  
  
  
    
      
      
        
      
      
      
    Voir la notice de l'article provenant de la source Math-Net.Ru
            
              			We consider a Goursat problem on classification nonlinear second order hyperbolic equations integrable by the Darboux method. In the work we study a class of hyperbolic equations with second order $y$-integral reduced by an differential substitution to equations with first order $y$-integral. It should be noted that Laine equations are in the considered class of equations. In the work we provide a second order $y$-integral for the second Laine equation and we find a differential substitution relating this equation with one of the Moutard equations. 
We consider a class of nonlinear hyperbolic equations possessing first order $y$-integrals and third order $x$-integrals. We obtain three conditions under which the equations in this class possess first order and third order integrals. We find the form of such equations and obtain the formulas for $x$- and $y$-integrals. In the paper we also provide differential substitutions relating Laine equations.
			
            
            
            
          
        
      
                  
                    
                    
                    
                        
Keywords: 
$x$- and $y$-integrals, differential substitutions.
Mots-clés : Laplace invariants
                    
                  
                
                
                Mots-clés : Laplace invariants
@article{UFA_2023_15_2_a2,
     author = {Yu. G. Voronova and A. V. Zhiber},
     title = {On a class of hyperbolic equations with third-order integrals},
     journal = {Ufa mathematical journal},
     pages = {20--30},
     publisher = {mathdoc},
     volume = {15},
     number = {2},
     year = {2023},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/UFA_2023_15_2_a2/}
}
                      
                      
                    Yu. G. Voronova; A. V. Zhiber. On a class of hyperbolic equations with third-order integrals. Ufa mathematical journal, Tome 15 (2023) no. 2, pp. 20-30. http://geodesic.mathdoc.fr/item/UFA_2023_15_2_a2/
