Answer
$y=x+1$
Work Step by Step
The tangent line at $x=0$ has slope $m=f^{\prime}(0)$
For $f^{\prime}(x)$, apply
$\displaystyle \frac{d}{dx}[\sinh u]=(\cosh u)u^{\prime}$ and $\displaystyle \frac{d}{dx}[e^{u}]=e^{u}\cdot u^{\prime}$
$y=f(x)=e^{\sinh x}$
$f^{\prime}(x)=e^{\sinh x}\cdot\cosh x$
$m=f^{\prime}(0)=e^{0}(1)=1$
At $(0,1),$ the tangent line is:
$y-y_{1}=m(x-x_{1})$
$y-1=1(x-0)$
$y=x+1$