Answer:
- f[1] = 60; f[n+1] = f[n] -30
- f[n] = 60 -30(n-1)
Explanation:
You observe that each term is 30 less than the previous one. This is the recursive rule. It also means the sequence is arithmetic with a common difference of -30.
Recursive equation
f[1] = 60; f[n+1] = f[n] -30
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Explicit equation
The general form of the explicit equation is ...
f(n) = f(1) +d(n -1)
Here, we have f(1) = 60 and d = -30, so your equation is ...
f(n) = 60 -30(n -1)