Value (mathematics)

In mathematics, value may refer to several, strongly related notions.

In general, a mathematical value may be any definite mathematical object. In elementary mathematics, this is most often a number – for example, a real number such as or an integer such as 42.

The value of a variable or a constant is any number or other mathematical object assigned to it. The value of a mathematical expression is the result of the computation described by this expression when the variables and constants in it are assigned values. The value of a function, given the value(s) assigned to its argument(s), is the quantity assumed by the function for these argument values.

For example, if the function is defined by , then assigning the value 3 to its argument yields the function value 10, since .

If the variable, expression or function only assumes real values, it is called real-valued. Likewise, a complex-valued variable, expression or function only assumes complex values.