9514 1404 393
Answer:
s(t) = 2^(t-1)
Step-by-step explanation:
The amount in the account is the sum of the series ...
1 + 1 +2 +4 +8 +16 +...
We note that terms after the first are a geometric sequence with a first term 1 and a common ratio 2. The sum of such a sequence is ...
Sn = a1×(r^n -1)/(r -1) . . . . where n is the number of terms being summed
For our values, this simplifies to ...
Sn = 1×(2^n -1)/(2 -1) = 2^n -1
We notice here that the account balance is 1 more than this sum, and that n = t-1, so the balance a(t) is ...
s(t) = 1 +(2^(t -1) -1)
s(t) = 2^(t -1) . . . . . . the function showing how much Jerry has
