How do you find the explicit rule for the geometric sequence #15, 3, 3/5, 3/25#?
1 Answer
Apr 10, 2017
By finding the common ratio(r) of the sequence and using the formula
The common ratio is
Explanation:
The ratio from 15 to 3 is 5:1; 15 is 5 times greater than 3. This is the same from 3 to
To check this, we plug each number into the sequence (starting with the number 1):
-
#15/5^((1)-1)# =#15/5^(0)# =#15/1# = 15 -
#15/5^((2)-1)# =#15/5^(1)# =#15/5# = 3 -
#15/5^((3)-1)# =#15/5^(2)# =#15/25# =#3/5# -
#15/5^((4)-1)# =#15/5^(3)# =#15/125# =#3/25#