Applicare la formula: $ax=b$$\to x=\frac{b}{a}$, dove $a=\cos\left(x\right)$, $b=\sin\left(z\right)$ e $x=\tan\left(y\right)$

Applicare la formula: $a=b$$\to inverse\left(a,a\right)=inverse\left(a,b\right)$, dove $a=\tan\left(y\right)$ e $b=\frac{\sin\left(z\right)}{\cos\left(x\right)}$

Applicare la formula: $\arctan\left(\tan\left(\theta \right)\right)$$=\theta $, dove $x=y$