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What is the 20th term in the following sequence?

-2, -6, -18, -54, -162...

User Teocali
by
4.9k points

1 Answer

2 votes

Answer:

-2324522934

Explanation:

These are the terms of a geometric sequence with n th term


a_(n) = a
(r)^(n-1)

where a is the first term and r the common ratio

r =
(-6)/(-2) = 3 and a = - 2, hence


a_(20) = - 2 ×
3^(19) = - 2324522934

User Murtuza Z
by
5.2k points