Applicare la formula: $\frac{a}{b}+\frac{c}{b}$$=\frac{a+c}{b}$, dove $a=- \infty $, $b=e^{\infty }$ e $c=-1$

Applicare la formula: $a+x$$=\infty sign\left(a\right)$, dove $a=- \infty $ e $x=-1$

Applicare la formula: $\frac{a}{n^{\infty }}$$=0$, dove $a/n^\infty=\frac{- \infty }{e^{\infty }}$, $a=- \infty $, $\infty=\infty $, $n^\infty=e^{\infty }$ e $n=e$