Disjoint union
= Disjoint union
{title2=$X\sqcup Y$}
{wiki}
The disjoint union tags the elements of its summands, for example $X\sqcup Y=(X\times\{0\})\cup(Y\times\{1\})$.
= Disjoint union
{title2=$X\sqcup Y$}
{wiki}
The disjoint union tags the elements of its summands, for example $X\sqcup Y=(X\times\{0\})\cup(Y\times\{1\})$.