Document Type: Research Paper

**Authors**

Department of Mathematics and computer science, Faculty of science, Lorestan University, Khorramabad, Iran.

**Abstract**

Let $$(Lv)(t)=\sum^{n} _{i,j=1} (-1)^{j} d_{j} \left( s^{2\alpha}(t) b_{ij}(t) \mu(t) d_{i}v(t)\right),$$ be a non-selfadjoint differential operator on the Hilbert space $L_{2}(\Omega)$ with Dirichlet-type boundary conditions. In continuing of papers [10-12], let the conditions made on the operator $ L$ be sufficiently more general than [11] and [12] as defined in Section $1$. In this paper, we estimate the resolvent of the operator $L$ on the one-dimensional space $ L_{2}(\Omega)$ using some analytic methods.

**Keywords**

**Main Subjects**

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