Answer
$$e^2-1$$
Work Step by Step
Given
$$ \int_{-1}^{1} e^{u+1} d u $$
Since
\begin{aligned}
\int_{-1}^{1} e^{u+1} d u&=\int_{-1}^{1} e^{u}\cdot e d u\\
&=e\int_{-1}^{1} e^{u}du\\
&= e[e^u]\bigg|_{-1}^1\\
&= e[e-\frac{1}{e}]\\
&= e\cdot \frac{e^2-1}{e}\\
&= e^2-1
\end{aligned}