Applicare la formula: $x+a=b$$\to x=b-a$, dove $a=-\sin\left(x\right)$, $b=1$, $x+a=b=\cos\left(y\right)-\sin\left(x\right)=1$, $x=\cos\left(y\right)$ e $x+a=\cos\left(y\right)-\sin\left(x\right)$

Applicare la formula: $ab$$=ab$, dove $ab=- -\sin\left(x\right)$, $a=-1$ e $b=-1$

Applicare la formula: $a=b$$\to inverse\left(a,a\right)=inverse\left(a,b\right)$, dove $a=\cos\left(y\right)$ e $b=1+\sin\left(x\right)$

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