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Subsection 0.1.2 Functions
Functions describe a special relationship between the elements of two sets. We cover functions more thoroughly in
Section 2.3 .
Let
\(A\) and
\(B\) be nonempty sets. A
function from
\(A\) to
\(B\text{,}\) denoted
\(f \colon A \to B\) is an assignment of exactly one element of
\(B\) to each element of
\(A\text{.}\)
The set
\(A\) is called the
domain of
\(f\) and the set
\(B\) is called the
codomain of
\(f\text{.}\)
