College Algebra

Question

help please

Write a rule for the nth term of the geometric sequence if r = 5 and  = 375.

an =

Answer 1

common ratio r=5

a2 = 5* a1

a3 = 5 * a2 = 5* 5*a1 = (5)^2 * a1

375 = a4 = 5* a3 = 5 *5*5 * a1

375/125 = a1

a = 3

An = 3*5^(n-1)

A1 = 3

A2 = 15

A3 = 75

A4 = 375