TURKISH JOURNAL OF MATHEMATICS, cilt.45, sa.4, ss.1847-1870, 2021 (SCI-Expanded)
In this paper, we study the inverse spectral problem for the quadratic differential pencils with discontinuity coefficient on [0, pi] with separable boundary conditions and the impulsive conditions at the point x = pi/2 . We prove that two potential functions on the interval [0, pi], and the parameters in the boundary and impulsive conditions can be determined from a sequence of eigenvalues for two cases: (i) The potentials are given on (0, pi/4 (1 + alpha) , (ii) The potentials are given on (pi/4 (1 + alpha) , pi) , where 0 < alpha < 1, respectively.