= \frac{1}
{\pi } + \frac{3}
{\pi }\left( {\left. {\frac{{x^2 \sin \pi x}}
{\pi }} \right|_0^1 - \frac{2}
{\pi }\int_0^1 {x\sin \pi xdx} } \right) = \frac{1}
{\pi } + \frac{3}
{\pi }\left( { - \frac{2}
{\pi } \cdot \frac{1}
{\pi }} \right)