Laplace Transform of Shifted Dirac Delta Function
Theorem
Let $\map \delta t$ denote the Dirac delta function.
The Laplace transform of $\map \delta {t - a}$ is given by:
- $\laptrans {\map \delta {t - a} } = e^{-a s}$
Proof 1
| \(\ds \laptrans {\map \delta {t - a} }\) | \(=\) | \(\ds \int_0^{\to +\infty} e^{-s t} \map \delta {t - a} \rd t\) | Definition of Laplace Transform | |||||||||||
| \(\ds \) | \(=\) | \(\ds e^{-s \times a}\) | Integral to Infinity of Shifted Dirac Delta Function by Continuous Function | |||||||||||
| \(\ds \) | \(=\) | \(\ds e^{-a s}\) |
$\blacksquare$
Also see
Sources
- 1965: Murray R. Spiegel: Theory and Problems of Laplace Transforms ... (previous) ... (next): Chapter $1$: The Laplace Transform: Laplace Transforms of Special Functions: $13$
- 1965: Murray R. Spiegel: Theory and Problems of Laplace Transforms ... (previous) ... (next): Appendix $\text B$: Table of Special Laplace Transforms: $113.$
- 1968: Murray R. Spiegel: Mathematical Handbook of Formulas and Tables ... (previous) ... (next): $\S 32$: Table of Special Laplace Transforms: $32.137$
- 2009: Murray R. Spiegel, Seymour Lipschutz and John Liu: Mathematical Handbook of Formulas and Tables (3rd ed.) ... (previous) ... (next): $\S 33$: Laplace Transforms: Table of Special Laplace Transforms: $33.137.$