\(\mathop \smallint \limits_{ - \frac{{3\pi }}{2}}^{ - \frac{\pi }{2}} \left[ {{{\left( {x + \pi } \right)}^3} + {{\cos }^2}\left( {x + 3\pi } \right)} \right]dx\) is equal to
1
\(\frac{{{\pi ^4}}}{{32}}\)
2
\(\frac{{{\pi ^4}}}{{32}} + \frac{\pi }{2}\)
3
\(\frac{\pi }{2}\)
4
\(\frac{\pi }{4} - 1\)