9514 1404 393
Answer:
2, 1, -1/2, -1/4, 1/8
Step-by-step explanation:
Use n = 1 through 4:
[tex]a_{1+1}=\dfrac{(-1)^{1+1}\cdot a_1}{2}\ \Rightarrow\ a_2=\dfrac{1\cdot2}{2}=1\\\\a_3=\dfrac{(-1)^3\cdot 1}{2}=-\dfrac{1}{2}\\\\a_4=\dfrac{(-1)^4\cdot(-\dfrac{1}{2})}{2}=-\dfrac{1}{4}\\\\a_5=\dfrac{(-1)^5\cdot(-\dfrac{1}{4})}{2}=\dfrac{1}{8}[/tex]
The first 5 terms are ...
2, 1, -1/2, -1/4, 1/8
