Complex Algebra

To avoid complex algebra, it is expedient to replace \(j\omega\) temporarily with \(s\) when working with \(\mathbf{H}(\omega)\) and replace \(s\) with \(j\omega\) at the end.

To avoid the complex algebra that explicitly appears in the Fourier transform, it is sometimes expedient to temporarily replace \(j\omega\) with \(s\) and then replace \(s\) with \(j\omega\) at the end.