Abstract :
Sufficient conditions are established for the oscillations of systems of hyperbolic
differential equations of the form
2 d
2 pŽt.uiŽx, t. Ý rŽt.uiŽx, t r. ž / t r 1
m s
aiŽt. uiŽx, t. Ý Ýai jkŽt. ujŽx, kŽt..
j 1 k 1
m l
qiŽx,t.uiŽx, t. Ý Ýqi jhŽx,t.ujŽx, hŽt..,
j 1 h 1
Žx, t. 0, . G, i 1, 2, . . . , m,
where is a bounded domain in Rn with a piecewise smooth boundary , and
is the Laplacian in Euclidean n-space Rn.
