Applicare la formula: $\frac{a}{b}\frac{c}{f}$$=\frac{ac}{bf}$, dove $a=\pi x$, $b=3$, $c=\sin\left(x\right)$, $a/b=\frac{\pi x}{3}$, $f=\sin\left(x\right)+\cos\left(2x\right)$, $c/f=\frac{\sin\left(x\right)}{\sin\left(x\right)+\cos\left(2x\right)}$ e $a/bc/f=\frac{\pi x}{3}\frac{\sin\left(x\right)}{\sin\left(x\right)+\cos\left(2x\right)}$