In mathematics, value may refer to several, strongly related notions:
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 replaced by some numbers.
The value of a function is the number implied by the function as a result of a particular number being assigned to its argument (also called the variable of the function).
For example, if the function
f
is defined by
f
(
x
)
=
2
x
2
−
3
x
+
1
, then, given the value 3 to the variable x yields the function value 10 (since indeed 2 · 32 – 3 · 3 + 1 = 10). This is denoted
f
(
3
)
=
10.
