Exponential equations can be used in modelling.

Examples include the use of \(e\) in continuous compound interest, radioactive decay, drug concentration decay, exponential growth as a model for population growth.

Limitations of exponential models include considering what is likely to happen at extreme ends of the model. For example, limitations of an exponential model for population growth include extraneous factors which take effect at very high populations, such as lack of resources to sustain the population.