Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
NCTM or The Math Forum.



Re: Onto Functions
Posted:
Dec 27, 2012 11:56 PM


A function is a relation mapping every element of one set to a unique element of another.
If f is a function mapping from set A to set B, we write:
f: A > B
or
for all x in A, f(x) is in B.
A function f mapping set A to set B is said to be onto (or surjective) iff
for all y in B, there exists an x in A such that f(x)=y.



