Applying the trigonometric identity: $\cot\left(\theta \right) = \frac{\cos\left(\theta \right)}{\sin\left(\theta \right)}$

Applicare la formula: $a\frac{b}{c}$$=\frac{ba}{c}$, dove $a=\sin\left(x\right)$, $b=\cos\left(x\right)$ e $c=\sin\left(x\right)$

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

Applicare l'identità trigonometrica: $1-\sin\left(\theta \right)^2$$=\cos\left(\theta \right)^2$

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