Function is, in mathematics, an expression, rule, or law that defines a
relationship between one variable (the independent variable) and
another variable (the dependent variable).
This relationship is commonly symbolized as , which is said
to be “ of ”, and are related such that for every , there is a
unique value of . That is, can not have more than one value for
the same .
If a variable is so related to a variable that whenever a numerical
value is assigned to , there is a rule according to which a unique value
of is determined, then is said to be a function of the independent
variable .
, Domain and Range of function
The domain and range of a function are the sets of all the -
coordinates and all the -coordinates of ordered pairs, respectively. For
example:
Examples
Cost function.
Revenue function.
Demand function.
Supply function.