Applicare la formula: $\ln\left(\frac{a}{b}\right)$$=\ln\left(a\right)-\ln\left(b\right)$, dove $a=x\sin\left(x\right)$ e $b=\sqrt{\sec\left(x\right)}$

Applicare la formula: $\ln\left(x^a\right)$$=a\ln\left(x\right)$, dove $a=\frac{1}{2}$ e $x=\sec\left(x\right)$

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

Applicare la formula: $\frac{a}{b}c$$=\frac{ca}{b}$, dove $a=1$, $b=2$, $c=-1$, $a/b=\frac{1}{2}$ e $ca/b=- \left(\frac{1}{2}\right)\ln\left(\sec\left(x\right)\right)$