On a Singularly Perturbed System of First-Order Partial Differential Equations
                
                
                
                    
                        
                            [1]
                            Oksana Flyud, Department of Mathematical Economics and Econometrics, Faculty of Mechanics and Mathematics, Ivan Franko National University of Lviv, Lviv, Ukraine.
                            
                         
                    
                 
                
                    The initial boundary value problem for a system of singularly perturbed linear partial differential equations of the first order in the plane is considered, the small parameter is a multiplier for various partial derivatives. Constructed and proved asymptotic expansion of the first order solution with the powers of a small parameter.
                
            
                
                    Hyperbolic System, Boundary Value Problem, Singular Perturbed, Asymptotic Expansions, Boundary Layer Function
                
                
                    
                        
                            
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