olemus
binaartehe \(\ast\), mille korral
\(x \ast y = y \ast x\) mis tahes argumentidega \(x\) ja \(y\)

ülevaateid
https://groupprops.subwiki.org/wiki/Commutative_binary_operation

https://en.wikipedia.org/wiki/Commutative_property

https://mathstats.uncg.edu/sites/pauli/112/HTML/section-60.html