SOLUTION: Consider the sequence. 4.5, −22.5, 112.5, −562.5, …

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Question 1158427: Consider the sequence.
4.5, −22.5, 112.5, −562.5, …
Found 2 solutions by Shin123, Edwin McCravy:
Answer by Shin123(626) About Me  (Show Source):
You can put this solution on YOUR website!
What about it?

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
4.5, −22.5, 112.5, −562.5, …



Since all those give the same answer, this is a geometric sequence with

first term = a1 = 4.5 and common ratio r = -5.

To get a formula for any term, we use the general formula for the nth term
of a geometric sequence, use this

matrix%281%2C3%2C%0D%0Aa%5Bn%5D%2C%22%22=%22%22%2Ca%5B1%5Dr%5E%28n-1%29%29

To get a formula for the sum of the first n terms, use this:




Edwin