Applying the trigonometric identity: $1-\cos\left(\theta \right)^2 = \sin\left(\theta \right)^2$

Applicare l'identità trigonometrica: $\csc\left(\theta \right)$$=\frac{1}{\sin\left(\theta \right)}$, dove $x=a$

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

Applicare la formula: $x^1$$=x$, dove $x=\sin\left(a\right)$