RO  EN
IMI/Publicaţii/BASM/Ediţii/BASM n.3 (13), 1993/

The uniform estimates for solutions of nonstrictly hyperbolic equation of second order with large parameter. (English)

Authors: Perjan A. V.

Abstract

We consider the equation $(P^2 - \lambda Q)u = f(x,t,\lambda)$, where $P \equiv {\partial / \partial t} +a(x,t) {\partial / \partial x} + b(x,t)$,\ \ $Q \equiv q_0(x,t) {\partial / \partial t} +q_1(x,t) {\partial / \partial x} + q_2(x,t)$ and $\lambda$ is a complex parameter, $|\lambda|\ge 1$. Uniform in $\lambda$ estimates of energetic type in case when $P^2$ and $Q$ form a nonstrictly hyperbolic pair are established for the solutions of this equation.

State University of Moldova
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