Applicare la formula: $\int\sin\left(ax\right)dx$$=-\left(\frac{1}{a}\right)\cos\left(ax\right)+C$, dove $a=3$

Applicare la formula: $\frac{a}{b}c$$=\frac{ca}{b}$, dove $a=1$, $b=3$, $c=-1$, $a/b=\frac{1}{3}$ e $ca/b=- \left(\frac{1}{3}\right)\cos\left(3x\right)$

Applicare la formula: $\left[x\right]_{a}^{b}$$=eval\left(x,b\right)-eval\left(x,a\right)+C$, dove $a=\pi $, $b=2\pi $ e $x=-\frac{1}{3}\cos\left(3x\right)$