Regular Trace Formula of Eigenvalues of a Discontinuous One-point Boundary Value Problem with Retarded Argument

In this study, we found a regular trace formula for the eigenvalues of the boundary value problem, which we created with the second-order differential equation with eigen parameter and discontinuity at x =π/2, which is an interior point of the finite range [0, π], and boundary conditions that also contain eigen parameter, and interface conditions.