Applicare l'identità trigonometrica: $\sec\left(\theta \right)$$=\frac{1}{\cos\left(\theta \right)}$

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

Applicare la formula: $\frac{a}{\frac{b}{c}}$$=\frac{ac}{b}$, dove $a=\tan\left(x\right)^2$, $b=1-\cos\left(x\right)$, $c=\cos\left(x\right)$, $a/b/c=\frac{\tan\left(x\right)^2}{\frac{1-\cos\left(x\right)}{\cos\left(x\right)}}$ e $b/c=\frac{1-\cos\left(x\right)}{\cos\left(x\right)}$

Applicare la formula: $\frac{\frac{a}{b}}{c}$$=\frac{a}{bc}$, dove $a=\sin\left(x\right)^2$, $b=\cos\left(x\right)$, $c=1-\cos\left(x\right)$, $a/b/c=\frac{\frac{\sin\left(x\right)^2}{\cos\left(x\right)}}{1-\cos\left(x\right)}$ e $a/b=\frac{\sin\left(x\right)^2}{\cos\left(x\right)}$