# Today I Learned

Some of the things I've learned every day since Oct 10, 2016

## 107: The Order of the Product of 2 Group Elements

Where $G$ is a group, and $a, b \in G$, it is always the case that

$|ab| = |ba|$.

That is, we can speak of ‘the’ order of the product of 2 group elements without worrying about which product it is.