Abstract:
Sufficient Conditions For Invariance Of Limit Point Case (Limit Circle Case) For The Sturm-Liouville Differential Operator ?=-D^2/(DX^2 )+Q At A Singular Point Under Perturbation Have Been Determined. In Particular It Is Proved That Under Bounded Below Perturbation Limit Point Case (Limit Circle Case) For The Sturm-Liouville Differential Operator At A Singular Point Remains Invariant.

Keywords:Limit Point Case, Limit Circle Case, Singular Point