Applicare la formula: $\frac{a}{b}$$=\frac{a}{b}\frac{radicalfactor\left(b\right)}{radicalfactor\left(b\right)}$, dove $a=2\left(1-x\right)$ e $b=\sqrt{4+x}$

Applicare la formula: $\frac{a}{b}\frac{c}{f}$$=\frac{ac}{bf}$, dove $a=2\left(1-x\right)$, $b=\sqrt{4+x}$, $c=\sqrt{4+x}$, $a/b=\frac{2\left(1-x\right)}{\sqrt{4+x}}$, $f=\sqrt{4+x}$, $c/f=\frac{\sqrt{4+x}}{\sqrt{4+x}}$ e $a/bc/f=\frac{2\left(1-x\right)}{\sqrt{4+x}}\frac{\sqrt{4+x}}{\sqrt{4+x}}$

Applicare la formula: $x\cdot x$$=x^2$, dove $x=\sqrt{4+x}$

Applicare la formula: $\left(x^a\right)^b$$=x$, dove $a=\frac{1}{2}$, $b=2$, $x^a^b=\left(\sqrt{4+x}\right)^2$, $x=4+x$ e $x^a=\sqrt{4+x}$