===== Closed monoid subset =====
==== Meta ====
| @#55CCEE: context     | @#55CCEE: $\langle\!\langle M,*\rangle\!\rangle$ ... monoid |
| @#FFBB00: definiendum | @#FFBB00: $S\in$ it |
| @#FFFDDD: for all     | @#FFFDDD: $x,y\in S$ |
| @#55EE55: postulate   | @#55EE55: $x*y\in S$ |

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=== Subset of ===
[[Monoid]]