Bounded solvability of pantograf type delay differential operators of first order and structure of spectrum

In this thesis, firstly all boundedly solvable extensions of the minimal operator generated by first order linear pantograph type delay differential-operator expression are described in terms of boundary values in Hilbert space of vector-functions defined on finite interval and structure of spectrum of such extensions is investigated. Later on, this research is generalized to first order multipoint linear pantograph type delay differential-operator expression. The results which have been obtained in this thesis are supported by examples.