Answer:
[tex]- \frac{1}{3} * 3^n[/tex]
Step-by-step explanation:
This is a geometric sequence/progression
Therefore, we use the formula [tex]a_{n} = \frac{a_{1} * r^n}{r}[/tex]
Where [tex]a_{1}[/tex] [tex]=[/tex] [tex]-1[/tex],
and [tex]r = 3[/tex]
[tex]a_{n} = \frac{-1 * 3^n}{3}[/tex]
[tex]a_{n} = -\frac{1}{3} * 3^n[/tex]