Category:Union Mappings

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This category contains results about Union Mappings.
Definitions specific to this category can be found in Definitions/Union Mappings.

Let:

$(1): \quad f_1: S_1 \to T_1$ be a mapping from $S_1$ to $T_1$
$(2): \quad f_2: S_2 \to T_2$ be a mapping from $S_2$ to $T_2$

Let $f_1$ and $f_2$ be combinable, that is, that they agree on $S_1 \cap S_2$.


Then the union mapping $f = f_1 \cup f_2$ of $f_1$ and $f_2$ is:

$f: S_1 \cup S_2 \to T_1 \cup T_2: \map f s = \begin{cases} \map {f_1} s : & s \in S_1 \\ \map {f_2} s : & s \in S_2 \end{cases}$