The quiz on Friday will consist of definitions, and will be brief. Your wording on a definition must be precise, and you will be required to give both a symbolic form and a verbal interpretation of the symbols. (Recall that an interpretation is a conceptual translation, not a symbolbysymbol transliteration.) You may be asked to produce examples or verify that something satisfies the requirements of a definition. The ideas you should know include:
$f\colon X \to Y$
$f^{1}\colon Y \to X$
$f\circ g$
$f$ is onetoone
$f$ is onto
$f$ is a bijection
$f=g$
${\rm id}_X$
$f(A)$
$f^{1}(B)$$R$ is a relation on $X$
$R$ is reflexive
$R$ is symmetric
$R$ is transitive
$\equiv$ is an equivalence relation on $X$
$[a]$
$X/\mathord{\sim}$

