Theorem cnvopab 5103

Description: The converse of a class abstraction of ordered pairs. (Contributed by NM, 11-Dec-2003.) (Proof shortened by Andrew Salmon, 27-Aug-2011.)

Assertion

Ref	Expression
cnvopab	|- `' { <. x , y >. | ph } = { <. y , x >. | ph }

Distinct variable group:   x, y

Allowed substitution hints:   ph( x, y)

Proof of Theorem cnvopab

Dummy variables z w are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		relcnv 5079	. 2 |- Rel `' { <. x , y >. | ph }
2		relopab 4822	. 2 |- Rel { <. y , x >. | ph }
3		opelopabsbALT 4323	. . . 4 |- ( <. w , z >. e. { <. x , y >. | ph } <-> [ z / y ] [ w / x ] ph )
4		sbcom2 2016	. . . 4 |- ( [ z / y ] [ w / x ] ph <-> [ w / x ] [ z / y ] ph )
5	3, 4	bitri 184	. . 3 |- ( <. w , z >. e. { <. x , y >. | ph } <-> [ w / x ] [ z / y ] ph )
6		vex 2779	. . . 4 |- z e. _V
7		vex 2779	. . . 4 |- w e. _V
8	6, 7	opelcnv 4878	. . 3 |- ( <. z , w >. e. `' { <. x , y >. | ph } <-> <. w , z >. e. { <. x , y >. | ph } )
9		opelopabsbALT 4323	. . 3 |- ( <. z , w >. e. { <. y , x >. | ph } <-> [ w / x ] [ z / y ] ph )
10	5, 8, 9	3bitr4i 212	. 2 |- ( <. z , w >. e. `' { <. x , y >. | ph } <-> <. z , w >. e. { <. y , x >. | ph } )
11	1, 2, 10	eqrelriiv 4787	1 |- `' { <. x , y >. | ph } = { <. y , x >. | ph }

Syntax hints:   = wceq 1373   [wsb 1786   e. wcel 2178   <.cop 3646   {copab 4120   `'ccnv 4692

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 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-14 2181  ax-ext 2189  ax-sep 4178  ax-pow 4234  ax-pr 4269

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-nf 1485  df-sb 1787  df-eu 2058  df-mo 2059  df-clab 2194  df-cleq 2200  df-clel 2203  df-nfc 2339  df-ral 2491  df-rex 2492  df-v 2778  df-un 3178  df-in 3180  df-ss 3187  df-pw 3628  df-sn 3649  df-pr 3650  df-op 3652  df-br 4060  df-opab 4122  df-xp 4699  df-rel 4700  df-cnv 4701

This theorem is referenced by:  mptcnv  5104  cnvxp  5120  mptpreima  5195  f1ocnvd  6171  cnvoprab  6343  mapsncnv  6805  lgsquadlem3  15671