Value (mathematics) - Citizendia

In mathematics, value commonly refers to the 'output' of a function. The Mathematical concept of a function expresses dependence between two quantities one of which is given (the independent variable, argument of the function In the most basic case, that of unary, single-valued functions, there is one input (the argument) and one output (the value of the function).

Example: If the function

f

is defined by prescribing that

f (x) = 2 x 2 - 3 x + 1

for each real number

x

, then the input 3 will yield the function value 10 (since indeed $2\cdot3^2-3\cdot3+1 = 10$ ).

The function $f$ of the example is real-valued, since each and every possible function value is real. The Mathematical concept of a function expresses dependence between two quantities one of which is given (the independent variable, argument of the function On the other hand, it is not injective, since different inputs may yield the same value; e. g. , $f ( - 1. 5) = 10$ , too.

In some contexts, for convenience, functions may be considered to have several arguments and/or several values; also cf. In Logic, Mathematics, and Computer science, the arity (synonyms include type, adicity, and rank) of a function In Mathematics, a multivalued function (shortly multifunction, other names set-valued function, set-valued map, multi-valued map the discussion in the article function. The Mathematical concept of a function expresses dependence between two quantities one of which is given (the independent variable, argument of the function However, strictly seen, this is not an extension, since such functions may be considered as having single families and/or sets as input or output.

Value is also used in other senses, e. g. , to specify a certain instance of a variable. A variable (ˈvɛərɪəbl is an Attribute of a physical or an abstract System which may change its Value while it is under Observation.

Example:

f (x) = 0

for two separate values of

x

, namely, for

x = 0. 5

and for

x = 1

See also