WEAK SOLUTION OF THE MIXED PROBLEM FOR THE SEMILINEAR PSEUDO-HYPERBOLIC EQUATIONS OF THE FOURTH ORDER WITH NON-SMOOTH COEFFICIENT

The article deals with the mixed problem for the semilinear pseudo-hyperbolic equation of the fourth order in terms of some coefficients to be quite smooth functional relations and some to have limited variation. The notion of weak solution is defined. The theorems of weak solution uniqueness for the considered problem are defined.