![abstract algebra - Why is commutativity optional in multiplication for rings? - Mathematics Stack Exchange abstract algebra - Why is commutativity optional in multiplication for rings? - Mathematics Stack Exchange](https://i.stack.imgur.com/UyIXV.jpg)
abstract algebra - Why is commutativity optional in multiplication for rings? - Mathematics Stack Exchange
![Sam Walters ☕️ on X: "Two quick examples of local rings (one commutative, one non-commutative). (The first one I thought up, the second is known from complex variables theory.) References. [1] S. Sam Walters ☕️ on X: "Two quick examples of local rings (one commutative, one non-commutative). (The first one I thought up, the second is known from complex variables theory.) References. [1] S.](https://pbs.twimg.com/media/FHzl9ZGVEAAlL0e.jpg)
Sam Walters ☕️ on X: "Two quick examples of local rings (one commutative, one non-commutative). (The first one I thought up, the second is known from complex variables theory.) References. [1] S.
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