Explain whether the following function $F(s)$ is a single$-$value function or multiple$-$value function.

$F(s)=cosh\frac{ssinh}{}$

where $=\sqrt[\phantom{2}]{s-1},cosh=\frac{e^{}{e}^{-}}{2},$ and $sinh=\frac{e^{}-e^{-}}{2}.$ Note that students get zero point if guessing an answer without detailed derivation.