Answer: 50
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Step-by-step explanation:
We're given f(1) = 3.2 which says the first term of the sequence is 3.2
To find the second term, we use the other equation, which is the recursive equation. Plug in x = 1 to get...
f(x+1) = 2.5*f(x)
f(1+1) = 2.5*f(1)
f(2) = 2.5*f(1)
f(2) = 2.5*3.2
f(2) = 8
The second term is 8. We multiplied the previous term (3.2) by the factor 2.5 to get this second term.
The third term is handled pretty much in a similar fashion
third term = 2.5*(second term)
third term = 2.5*8
third term = 20
Lastly, the fourth term f(4) is...
f(x+1) = 2.5*f(x)
f(3+1) = 2.5*f(3)
f(4) = 2.5*f(3)
f(4) = 2.5*20
f(4) = 50
The fourth term is 50.
The first four terms are: 3.2, 8, 20, 50