Theorem iscmn 13662

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

Hypotheses

Ref	Expression
iscmn.b	|- B = ( Base ` G )
iscmn.p	|- .+ = ( +g ` G )

Assertion

Ref	Expression
iscmn	|- ( G e. CMnd <-> ( G e. Mnd /\ A. x e. B A. y e. B ( x .+ y ) = ( y .+ x ) ) )

Distinct variable groups:   x, y, B   x, G, y

Allowed substitution hints:   .+ ( x, y)

Proof of Theorem iscmn

Dummy variable g is distinct from all other variables.

Step	Hyp	Ref	Expression
1		fveq2 5578	. . . . 5 |- ( g = G -> ( Base ` g ) = ( Base ` G ) )
2		iscmn.b	. . . . 5 |- B = ( Base ` G )
3	1, 2	eqtr4di 2256	. . . 4 |- ( g = G -> ( Base ` g ) = B )
4		raleq 2702	. . . . 5 |- ( ( Base ` g ) = B -> ( A. y e. ( Base ` g ) ( x ( +g ` g ) y ) = ( y ( +g ` g ) x ) <-> A. y e. B ( x ( +g ` g ) y ) = ( y ( +g ` g ) x ) ) )
5	4	raleqbi1dv 2714	. . . 4 |- ( ( Base ` g ) = B -> ( A. x e. ( Base ` g ) A. y e. ( Base ` g ) ( x ( +g ` g ) y ) = ( y ( +g ` g ) x ) <-> A. x e. B A. y e. B ( x ( +g ` g ) y ) = ( y ( +g ` g ) x ) ) )
6	3, 5	syl 14	. . 3 |- ( g = G -> ( A. x e. ( Base ` g ) A. y e. ( Base ` g ) ( x ( +g ` g ) y ) = ( y ( +g ` g ) x ) <-> A. x e. B A. y e. B ( x ( +g ` g ) y ) = ( y ( +g ` g ) x ) ) )
7		fveq2 5578	. . . . . . 7 |- ( g = G -> ( +g ` g ) = ( +g ` G ) )
8		iscmn.p	. . . . . . 7 |- .+ = ( +g ` G )
9	7, 8	eqtr4di 2256	. . . . . 6 |- ( g = G -> ( +g ` g ) = .+ )
10	9	oveqd 5963	. . . . 5 |- ( g = G -> ( x ( +g ` g ) y ) = ( x .+ y ) )
11	9	oveqd 5963	. . . . 5 |- ( g = G -> ( y ( +g ` g ) x ) = ( y .+ x ) )
12	10, 11	eqeq12d 2220	. . . 4 |- ( g = G -> ( ( x ( +g ` g ) y ) = ( y ( +g ` g ) x ) <-> ( x .+ y ) = ( y .+ x ) ) )
13	12	2ralbidv 2530	. . 3 |- ( g = G -> ( A. x e. B A. y e. B ( x ( +g ` g ) y ) = ( y ( +g ` g ) x ) <-> A. x e. B A. y e. B ( x .+ y ) = ( y .+ x ) ) )
14	6, 13	bitrd 188	. 2 |- ( g = G -> ( A. x e. ( Base ` g ) A. y e. ( Base ` g ) ( x ( +g ` g ) y ) = ( y ( +g ` g ) x ) <-> A. x e. B A. y e. B ( x .+ y ) = ( y .+ x ) ) )
15		df-cmn 13655	. 2 |- CMnd = { g e. Mnd | A. x e. ( Base ` g ) A. y e. ( Base ` g ) ( x ( +g ` g ) y ) = ( y ( +g ` g ) x ) }
16	14, 15	elrab2 2932	1 |- ( G e. CMnd <-> ( G e. Mnd /\ A. x e. B A. y e. B ( x .+ y ) = ( y .+ x ) ) )

Syntax hints:   /\ wa 104   <-> wb 105   = wceq 1373   e. wcel 2176   A.wral 2484   ` cfv 5272  (class class class)co 5946   Basecbs 12865   +g cplusg 12942   Mndcmnd 13281  CMndccmn 13653

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-ext 2187

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-nf 1484  df-sb 1786  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ral 2489  df-rex 2490  df-rab 2493  df-v 2774  df-un 3170  df-sn 3639  df-pr 3640  df-op 3642  df-uni 3851  df-br 4046  df-iota 5233  df-fv 5280  df-ov 5949  df-cmn 13655

This theorem is referenced by:  isabl2  13663  cmnpropd  13664  iscmnd  13667  cmnmnd  13670  cmncom  13671  ghmcmn  13696  iscrng2  13810