Mathematics

Problem

The value of

\int_{-\pi/2}^{\pi/2} \frac{x^2 \cos x}{1 + e^x} dx

is equal to a.

\frac{\pi^2}{4} - 2

\frac{\pi^2}{4} + 2

\pi^2 - e^{-\pi/2}

\pi^2 + e^{\pi/2}