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General boundary value problem for elliptic systems of second order with constant coefficients. II

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... The classical method of studying boundary value problems for elliptic equations and systems on a plane is based on representing the solutions of elliptic equations in terms of analytic functions, which allows one to reduce the matter to the study of the boundary value problems of function theory. For elliptic systems with constant leading coefficients, a method was developed by A. V. Bitsadze [1] (see also [2,3]). In the Bitsadze representation of solutions to elliptic systems, along with analytical functions, its derivatives up to a certain order are also involved. ...
... Vishik [18], who called them strongly elliptic. They are determined by the positive definiteness condition for the matrix p(t) given in (2) for an arbitrary t ∈ R. Note that this condition is equivalent [19] to det(a 0 α + 2a 1 β + a 2 γ) = 0 for β 2 − αγ < 0. ...
... with the eigenvalues being coincided with the roots of the characteristic polynomial (2). It reduces to the Jordan form ...
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The role played by explicit formulas for solving boundary value problems for elliptic equations and systems is well known. In this paper, explicit formulas for a general solution of the Dirichlet problem for second-order elliptic systems in the unit disk are given. In addition, an iterative method for solving this problem for systems with respect to two unknown functions is described, and an integral representation of the Poisson type is obtained by applying this method.
... The second method is based on representing solutions of elliptic equations through analytic functions, which makes it possible to reduce the task to studying boundary-value problems in terms of the theory of functions. For elliptic equations in a plane with real analytical coefficients, this method was developed by Vekua (see [22]); for elliptic systems with constant coefficients -by Bitsadze [6] (see also [18,21]). ...
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