Final answer:
A function is a mathematical connection in which there is exactly one output value for every input value between two sets of integers. It describes a relationship between variables and is often represented using equations.
Step-by-step explanation:
Every input, also known as a domain element, has a single output that is related to it mathematically. This relationship is known as a function. It describes a relationship between the input and the output values. For example, if we have a function f(x) = 2x, for every input value x, we get an output value that is twice the input value.
Functions are often represented using equations, such as y = mx + b for linear functions. The equation allows us to understand the relationship between the independent variable (x) and the dependent variable (y).
In the context of economic models, functions can be used to describe the relationship between different variables, such as the relationship between price and quantity demanded.