Applicare la formula: $\frac{a}{b}\frac{c}{f}$$=\frac{ac}{bf}$, dove $a=2x$, $b=x-1$, $c=3x+5$, $a/b=\frac{2x}{x-1}$, $f=x^2$, $c/f=\frac{3x+5}{x^2}$ e $a/bc/f=\frac{2x}{x-1}\frac{3x+5}{x^2}$

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