Applicare la formula: $a+b$$=a+b$, dove $a=5$, $b=2$ e $a+b=5+2$

Applicare la formula: $a^nb^n$$=\left(ab\right)^n$, dove $a=7$, $b=6$ e $n=\frac{1}{2}$

Applicare la formula: $ab$$=ab$, dove $ab=7\cdot 6$, $a=7$ e $b=6$

Simplify $\left(\sqrt{42}\right)^{-1}$ using the power of a power property: $\left(a^m\right)^n=a^{m\cdot n}$. In the expression, $m$ equals $\frac{1}{2}$ and $n$ equals $-1$

Applicare la formula: $\frac{a}{b}c$$=\frac{ca}{b}$, dove $a=1$, $b=2$, $c=-1$, $a/b=\frac{1}{2}$ e $ca/b=-\frac{1}{2}$