Theorem fndmdifcom 5623

Description: The difference set between two functions is commutative. (Contributed by Stefan O'Rear, 17-Jan-2015.)

Assertion

Ref	Expression
fndmdifcom	|- ( ( F Fn A /\ G Fn A ) -> dom ( F \ G ) = dom ( G \ F ) )

Proof of Theorem fndmdifcom

Dummy variable x is distinct from all other variables.

Step	Hyp	Ref	Expression
1		necom 2431	. . . 4 |- ( ( F ` x ) =/= ( G ` x ) <-> ( G ` x ) =/= ( F ` x ) )
2	1	a1i 9	. . 3 |- ( x e. A -> ( ( F ` x ) =/= ( G ` x ) <-> ( G ` x ) =/= ( F ` x ) ) )
3	2	rabbiia 2723	. 2 |- { x e. A | ( F ` x ) =/= ( G ` x ) } = { x e. A | ( G ` x ) =/= ( F ` x ) }
4		fndmdif 5622	. 2 |- ( ( F Fn A /\ G Fn A ) -> dom ( F \ G ) = { x e. A | ( F ` x ) =/= ( G ` x ) } )
5		fndmdif 5622	. . 3 |- ( ( G Fn A /\ F Fn A ) -> dom ( G \ F ) = { x e. A | ( G ` x ) =/= ( F ` x ) } )
6	5	ancoms 268	. 2 |- ( ( F Fn A /\ G Fn A ) -> dom ( G \ F ) = { x e. A | ( G ` x ) =/= ( F ` x ) } )
7	3, 4, 6	3eqtr4a 2236	1 |- ( ( F Fn A /\ G Fn A ) -> dom ( F \ G ) = dom ( G \ F ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1353   e. wcel 2148   =/= wne 2347   {crab 2459   \ cdif 3127   dom cdm 4627   Fn wfn 5212   ` cfv 5217

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-in1 614  ax-in2 615  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-14 2151  ax-ext 2159  ax-sep 4122  ax-pow 4175  ax-pr 4210

This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1461  df-sb 1763  df-eu 2029  df-mo 2030  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-ne 2348  df-ral 2460  df-rex 2461  df-rab 2464  df-v 2740  df-sbc 2964  df-dif 3132  df-un 3134  df-in 3136  df-ss 3143  df-pw 3578  df-sn 3599  df-pr 3600  df-op 3602  df-uni 3811  df-br 4005  df-opab 4066  df-id 4294  df-xp 4633  df-rel 4634  df-cnv 4635  df-co 4636  df-dm 4637  df-iota 5179  df-fun 5219  df-fn 5220  df-fv 5225

This theorem is referenced by: (None)