Constant (mathematics)

As an adjective, it refers to non-variance (i.e. unchanging with respect to some other value); as a noun, it has two different meanings: For example, a general quadratic function is commonly written as: where a, b and c are constants (coefficients or parameters), and x a variable—a placeholder for the argument of the function being studied.

A more explicit way to denote this function is which makes the function-argument status of x (and by extension the constancy of a, b and c) clear.

More generally, any polynomial term or expression of degree zero (no variable) is a constant.

The context-dependent nature of the concept of "constant" can be seen in this example from elementary calculus: "Constant" means not depending on some variable; not changing as that variable changes.

Some values occur frequently in mathematics and are conventionally denoted by a specific symbol.

Examples include: In calculus, constants are treated in several different ways depending on the operation.