Solution. Let h(x) = e^{\sin(x)}, f(u) = e^u and g(x) = \sin(x). We will use the chain rule:
\begin{align*} h'(x) = f'(g(x))g'(x). \end{align*}
\begin{align*} f'(u) = e^u \quad \text{and} \quad g'(x) = \cos(x). \end{align*}
\begin{align*} h'(x) &= f'(g(x))g'(x) \\ &= e^{\sin(x)}\cos(x) \\ &= \cos(x)e^{\sin(x)} \end{align*}