$\mathcal{A}$ and if $x,y,z \in \mathcal{A}$, then
$\alg{\set{x,y,z}}$ is the smallest subalgebra of $\mathcal{A}$
containing the set $\set{x,y,z}$.
$\mathcal{A}$ and if $x,y,z \in \mathcal{A}$, then
$\alg{\set{x,y,z}}$ is the smallest subalgebra of $\mathcal{A}$
containing the set $\set{x,y,z}$.