## Intermediate Algebra (6th Edition)

$\frac{1}{8}$
To calculate $a_n$, we plug in $n$ to the general formula. To calculate the result, we use PEMDAS (parentheses, exponentation, multiplication, division, addition, subtraction) to determine which operation is applied first. $a_{8} = \frac{(-1)^8}{8} = \frac{1}{8}$