Chapter 11 - Section 11.1 - Sequences - 11.1 Exercises - Page 735: 8

$-\frac{1}{4},\frac{1}{16},-\frac{1}{64},\frac{1}{256},-\frac{1}{1024}$

$a_{n}=\frac{(-1)^{n}}{4^{n}}$ Substitute $1,2,3,4,5$ to $n$: $a_{1}=\frac{(-1)^{1}}{4^{1}}=-\frac{1}{4}$ $a_{2}=\frac{(-1)^{2}}{4^{2}}=\frac{1}{16}$ $a_{3}=\frac{(-1)^{3}}{4^{3}}=-\frac{1}{64}$ $a_{4}=\frac{(-1)^{4}}{4^{4}}=\frac{1}{256}$ $a_{5}=\frac{(-1)^{5}}{4^{5}}=-\frac{1}{1024}$