Applications of Exponential and Logarithmic Functions

Population can fluctuate positively or negatively and can be modeled using an exponential function. 

A realistic model of exponential growth must dampen when approaching a certain value. This limited growth is modelled with the logistic growth model: $P(t)=\frac{c}{1+a\cdot e^{-bt}}$.

Compound interest is accrued when interest is earned not only on principal, but on previously accrued interest: it is interest on interest.

Exponential decay is the result of a function that decreases in proportion to its current value.