解析

PlanetMathで調べたもの
Wikiで調べた方はこちら

Multivalued function（PlanetMath）

multivalued function: $f:A \Rightarrow B$

function: $f:A \rightarrow P(B)$

injection

$f:A \Rightarrow B$ is injective if $f(a) = f(b) \rightarrow a=b$

ablosutely injective if $a\neq b \rightarrow f(a) \cap f(b) = \phi$

surjection

$f:A \Rightarrow B$ is surjective if $\forall b \in B \, \exist a\in A \it{ s.t. } b \in f(a)$

bijection

injective and surjective

composition
identity

KABIRAの日記

多価関数