Metamath Proof Explorer


Theorem cmnmnd

Description: A commutative monoid is a monoid. (Contributed by Mario Carneiro, 6-Jan-2015)

Ref Expression
Assertion cmnmnd G CMnd G Mnd

Proof

Step Hyp Ref Expression
1 eqid Base G = Base G
2 eqid + G = + G
3 1 2 iscmn G CMnd G Mnd x Base G y Base G x + G y = y + G x
4 3 simplbi G CMnd G Mnd