= \frac{1}
{\pi } + \frac{2}
{\pi }\left( {\left. {\frac{{x\sin \pi x}}
{\pi }} \right|_0^1 - \frac{1}
{\pi }\int_0^1 {\sin \pi xdx} } \right) - \frac{1}
{2 \pi} =