Answer:
an = 3^(n-1)
Step-by-step explanation:
(1,1) (2,3) (3,9)
The y values
1,3,9,.....
We are multiplying by 3 each time
This is a geometric sequence
The formula for a geometric sequence is
an = a1 (r) ^ (n-1)
where a1 is the first term r is the common ratio ( or what we multiply by) and n is the term number
a1 = 1
r =3
an = 1* (3) ^ (n-1)
an = 3^(n-1)