In this paper, we construct a characteristic determinant of the spectral problem of a first-order differential equation on an interval with an integral perturbation in the boundary value condition, which is an entire analytic function of the spectral parameter. Based on the formula for the characteristic determinant, conclusions are drawn about the asymptotic behavior of the spectrum of the perturbed spectral problem depending on the modulus of continuity of the subinteral function.

Keywords:
## differentiation operator, continuous functions, entire functions, boundary value conditions, integral perturbation, characteristic determinant, eigenvalues, zeros, asymptotics, continuity module loaded differential equation.,

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**ISSN:**2667-7660**Yayın Aralığı:**Yılda 2 Sayı**Başlangıç:**2019**Yayıncı:**Hüseyin ÇAKALLI

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