Answer:
The sequence above is a geometric sequence
For an nth in a geometric sequence
[tex]u(n) = a {r}^{n - 1} [/tex]
where n is the number of terms
a is the first term
r is the common ratio
From the question
a = 45
r = 15 / 45
The explicit formula for the sequence is
U(n) = 45(1/3)^n-1
Hope this helps you
