Left Operation is Associative

Theorem

The left operation is associative:

$\forall x, y, z: \paren {x \gets y} \gets z = x \gets \paren {y \gets z}$


Proof

\(\ds x \gets \paren {y \gets z}\) \(=\) \(\ds x \gets y\) Definition of Left Operation
\(\ds \) \(=\) \(\ds x\) Definition of Left Operation


\(\ds \paren {x \gets y} \gets z\) \(=\) \(\ds x \gets z\) Definition of Left Operation
\(\ds \) \(=\) \(\ds x\) Definition of Left Operation

$\blacksquare$


Also see


Sources

  • 1965: Seth Warner: Modern Algebra ... (previous) ... (next): Chapter $\text I$: Algebraic Structures: $\S 2$: Compositions: Example $2.4$
  • 1965: Seth Warner: Modern Algebra ... (previous) ... (next): Chapter $\text I$: Algebraic Structures: $\S 2$: Compositions: Exercise $2.9$