Sum formulas
:
\begin{eqnarray*} \sinh ( A+B) &=&\sinh A\cosh B+\cosh A\sinh B \\ \cosh ( A+B) &=&\cosh A\cosh B+\sinh A\sinh B \end{eqnarray*}
Even/odd properties
:
\begin{eqnarray*} \sinh ( -A) =-\sinh A\qquad \cosh ( -A) =\cosh A \end{eqnarray*}