Composition of relations
= Composition of relations
{title2=$R\circ S=\{(x,z):\exists y,\ xRy,\ ySz\}$}
{wiki}
= Compositions of relations
{synonym}
This convention composes paths in their written order; some sources instead reverse that convention. <Composition of relations> is associative. Taking inverse relations reverses the order: $(R\circ S)^{-1}=S^{-1}\circ R^{-1}$.
// Target: foundations-of-mathematics.bigb