I've just read the section on Exponential Growth and Decay functions. Then I was doing exercises from that section and to solve my problems I often used this function
y = Ce^(kt)
which is an Exponential Growth and Decay function.
Then I was trying to solve a problem about Compound interest (from the same section) and again I was trying to use the same function above. But when I looked to check my answers, I was surprised as they used another function to solve the problem:
Amount = P(1 + r/n)^nt where t in years, r is rate at which the amount is compounded, and n is the proportionality constant (1, 12, or 365) I believe
So, my question is how these two formulas are different? Why they used another formula to find a compound interest, and why y = Ce^(kt) cannot be used instead?