Answer:
[tex]a_{n}[/tex] = 3*[tex]3^{n-1}[/tex]
Step-by-step explanation:
We notice that the common ratio = 9/3 = 3
and 27/9 = 3
the first term is 3
so
a_n = a_1 * r^(n-1) is the formula.
a_n = 3 * 3^(n-1)