Answer:
[tex]a_{n} = \frac{8}{2^{n-1} }[/tex]
Step-by-step explanation:
A geometric sequence has a constant ratio (r) and is defined by:
[tex]a_n=a_1r^{n-1}[/tex]
Since the first value is 8, [tex]a_{1}[/tex] = 8.
[tex]a_n=8r^{n-1}[/tex]
We can also see that a_n is double that of the next value in the sequence [tex](a_{n} = 2a_{n+1}})[/tex], hence r = 1/2
[tex]a_n=8\left(\frac{1}{2}\right)^{n-1}[/tex] or
[tex]a_{n} = \frac{8}{2^{n-1} }[/tex]
