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

Applicare la formula: $\frac{\frac{a}{b}}{c}$$=\frac{a}{bc}$, dove $a=1-x$, $b=x$, $c=x-1$, $a/b/c=\frac{\frac{1-x}{x}}{x-1}$ e $a/b=\frac{1-x}{x}$

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