Question

Given a term in a geometric sequence and the common ratio find the first five terms, the explicit formula, and the recursive formula. a1=4,r=5

Answer 1

explicit
an=a1(r)^(n-1)
an=4(5)^(n-1)

recursive

`a_n=5a_(n-1)` where a1=4

first 5 terms are
4,20,100,500,2500