Potential for Incorrect Solutions of Continuous-Time LTI System Problems When Using Eigenfunctions

The concept of eigenfunctions for a linear time-invariant system is emphasized in this short paper. It is pointed out that when the concept of eigenfunctions is used, incorrect results may be obtained if the region of convergence of the system function is overlooked. As a consequence, incorrect solutions can be obtained, as was the case for an example found in a widely used textbook.