$$\displaystyle\int_{ -1 }^{ 1 } (1- \frac{ \cos 2 \theta x }{ 2 \theta } ) d x$$
$\frac{-\frac{\sin(2\theta )}{\theta ^{2}}+4}{2}$
$\frac{-\theta \cos(2\theta )+\sin(2\theta )}{\theta ^{3}}$
