#help
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As we have exponential growth from the year t0 = 2007, we can write the amount at year n as:
N(t) = N0 a^(t - t0), where N0 = N(t0) and a is a constant we don't know.
Then, suppose we have the amount for two values of t:
N1 = N(t1) = N0 a^(t1 - t0)
N2 = N(t2) = N0 a^(t2 - t0)
Let's take the logarithm of each equation.
ln(N1) = ln(N0) + (t1 - t0) ln(a)
ln(N2) = ln(N0) + (t2 - t0) ln(a)
Now, let's multiply the first equation by (t2 - t0) and the second by (t1 - t0).
(t2 - t0)ln(N1) = (t2 - t0)ln(N0) + (t2 - t0)(t1 - t0) ln(a)
(t1 - t0)ln(N2) = (t1 - t0)ln(N0) + (t2 - t0)(t1 - t0) ln(a)
Now, let's subtract the second equation from the first.
(t2 - t0)ln(N1) - (t1 - t0)ln(N2) = (t2 - t1)ln(N0)
From here we get:
ln(N0) = ((t2 - t0)ln(N1) - (t1 - t0)ln(N2))/(t2 - t1)
So, now you can get N0 from here by potentiating and substituting the given values.
Wha
What?
I don’t get it
Which part?
We are just performing algebraic manipulation to solve the following system for N0 and a:
N1 = N0 a^(t1 - t0)
N2 = N0 a^(t2 - t0)
But since we don't need a specifically, we can just find N0 and stop there.
What’s the answer then?
As I said, potentiate the last equation and substitute the given values.
I got it wrong
What did you get?
Nvm I got it