In mathematics, the range of a function is the set of all values produced by a function. Sometimes called the image.
Given a function
, the set f(A) is called the range of f.
The range is not to be confused with the codomain B. Generally the range is only a subset of the codomain.
Example
Let the function f be a function on the real numbers:
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defined by
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The codomain of f is R, but clearly f(x) never takes negative values, and thus the range is in fact the set R+—non-negative reals, i.e. the interval [0,∞):
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See also
codomain, domain (mathematics), injective function, surjective function, bijective function