add dirac delta laplace

Signed-off-by: Thomas Gassmann <tgassmann@student.ethz.ch>

complex-analysis/complex.tex

@@ -726,6 +726,7 @@ \subsubsection{Laplace-Transformationen}
   $\int_0^t f(\tau) g(t-\tau) d\tau$ & $\mathcal{L}[f](s) \cdot \mathcal{L}[g](s)$ \\
   $\cosh(at)$ & $\frac{s}{s^2 - a^2}, \; \Re(s) >  a$\\
   $\sinh(at)$ & $\frac{a}{s^2 - a^2}, \; \Re(s) >  a$\\
+  $\delta(t - a)$ & $e^{-as}$\\
   \bottomrule
   \end{tabularx}
 \end{center}