Operational matrix and their applications for solving time-varying delay systems

The purpose of this paper is to provide a generalized formulation for Hat basis functions and to present the operational matrices for finding the approximate solution for time-invariant delay systems‎. ‎From this prospect‎, ‎the hat basic functions of integration‎, ‎delay‎, ‎product‎, ‎and dual are derived‎, ‎which are utilized to practically reduce the time-varying delay systems solution to the simplest system of algebraic equations‎. ‎The numerical results compared and tabled with previous works showcase the method's simplicity‎, ‎clarity‎, ‎and effectiveness through the three examples.