Abstract:
The paper is a continuation of [7] and devoted to high-order hyperbolic operators whose symbols have no zeros in a strip δ<sub>-</sub>< lm$\tau$ <δ<sub>+</sub>, where $\tau$ is the variable duel to the time variable t. Two types of results are presented. In the case δ<sub>+</sub> = +\infty (or δ<sub>-</sub> = -\infty ) for the corresponding operator we prove the unique solvability of the Cauchy problem on the semiaxis ±t ≥ 0 in the spaces of functions decreasing exponentially as t → ±\infty . In the case of finite δ<sub>±</sub> the unique solvability on the whole time axis in the spaces of bounded in t functions is proved. The results of this paper are based on the estimates are obtained in [7].