Question

which expression is equivalent to $7^{-10}$?
$\frac{1}{7^{-10}}$ $\frac{1}{7^{10}}$ $-\frac{7}{10}$ $\frac{7}{10}$

Explanation:

Step1: Recall negative exponent rule

For any non-zero base $a$ and integer $n$, $a^{-n} = \frac{1}{a^n}$.

Step2: Apply rule to $7^{-10}$

Substitute $a=7$, $n=10$ into the rule:
$7^{-10} = \frac{1}{7^{10}}$

Answer:

$\frac{1}{7^{10}}$ (corresponding to the second option)