Applicare la formula: $a+\frac{b}{c}$$=\frac{b+ac}{c}$, dove $a=\frac{1}{x}$, $b=1$, $c=2$, $a+b/c=\frac{1}{x}+\frac{1}{2}$ e $b/c=\frac{1}{2}$

Applicare la formula: $a+\frac{b}{c}$$=\frac{b+ac}{c}$, dove $a=1$, $b=2$, $c=x$, $a+b/c=1+\frac{2}{x}$ e $b/c=\frac{2}{x}$

Applicare la formula: $a+\frac{b}{c}$$=\frac{b+ac}{c}$, dove $a=-x$, $b=4$, $c=x$, $a+b/c=\frac{4}{x}-x$ e $b/c=\frac{4}{x}$

Applicare la formula: $\frac{\frac{a}{b}}{\frac{c}{f}}$$=\frac{af}{bc}$, dove $a=4-x^2$, $b=x$, $a/b/c/f=\frac{\frac{4-x^2}{x}}{\frac{\frac{2+x}{x}}{2}}$, $c=\frac{2+x}{x}$, $a/b=\frac{4-x^2}{x}$, $f=2$ e $c/f=\frac{\frac{2+x}{x}}{2}$