Question 194642: Do exponential functions only model phenomena that grow, or can they also model phenomena that decay? Explain what is different in the form of the function in each case.
Answer by RAY100(1637)   (Show Source):
You can put this solution on YOUR website! if we use the form,, y = C(1 + r)^t,, for exponential growth,,this makes sense,
as t grows, y also grows but at exponential rate. If r=.2, as t grows 1, y grows 1.2 C,
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if we look at the form , y=C(1-r)^t,,,for exponential decay,
as t grows, y decays at an exponential rate. If r=.2, as t grows 1, y decays to .8C.
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to remember this think of it as the discount vs tax increase.
we use (1+r) for taxes (increases),,,,and (1-r) for discounts.
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Good Question,,,,keep up good work
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