The image of a map (a.k.a. function, transformation, etc.) 
is the set of values attained
as its argument varies over the domain 
. It is also called the range of
and is written
 |
More generally, the image of a subset 
is 
(Halmos 1974, p. 31). The image 
is a subset
of the codomain 
and need not equal 
.
If the domain of a function 
contains an interval ![[a,b]](/images/equations/Image/Inline10.svg)
, then ![f([a,b])](/images/equations/Image/Inline11.svg)
denotes the image of that interval.
Formally,
![f([a,b])={y: exists x in [a,b] such that f(x)=y}.](/images/equations/Image/NumberedEquation2.svg) |
