more laplace transforms

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

complex-analysis/complex.tex

@@ -1930,6 +1930,8 @@ \subsubsection{Laplace-Transformationen}
   $\int_0^t f(\tau)d\tau$&$\frac{1}{s}\cdot \mathcal{L}[f](s)$\\
   $\cosh(at)$ & $\frac{s}{s^2 - a^2}, \; \Re(s) >  a$\\
   $\sinh(at)$ & $\frac{a}{s^2 - a^2}, \; \Re(s) >  a$\\
+  $t \cosh(at)$ & $\frac{s^2 + a^2}{(s^2 - a^2)^2}, \; \Re(s) >  a$\\
+  $t \sinh(at)$ & $\frac{2as}{(s^2 - a^2)^2}, \; \Re(s) >  a$\\
   $\delta(t - a)$ & $e^{-as}$\\
   \bottomrule
   \end{tabularx}