Find the 9th term of the geometric sequence whose common ratio is 1/3 and whose first term is 2.
1 answer:
Answer:
2/6561
Step-by-step explanation:
Geometric sequence formula :
where an = nth term, a1 = first term , r = common ratio and n = term position
given ratio : 1/3 , first term : 2 , given this we want to find the 9th term
to do so we simply plug in what we are given into the formula
recall formula :
define variables : a1 = 2 , r = 1/3 , n = 9
plug in values
a9 = 2(1/3)^(9-1)
subtract exponents
a9 = 2(1/3)^8
evaluate exponent
a9 = 2 (1/6561)
multiply 2 and 1/6561
a9 = 2/6561
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