Applicare l'identità trigonometrica: $\tan\left(\theta \right)$$=\frac{\sin\left(\theta \right)}{\cos\left(\theta \right)}$

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

Applicare la formula: $1x$$=x$, dove $x=\cos\left(x\right)$

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