9514 1404 393
Answer:
an = 400·(1/2)^(n -1)
Step-by-step explanation:
The first term of the sequence is a1 = 400. The common ratio is r = 200/400 = 1/2.
The general term of a geometric sequence is ...
an = a1·r^(n-1)
Filling in the applicable values, we get the explicit formula ...
an = 400·(1/2)^(n -1)
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This can be simplified to ...
an = 800/2^n
