Theorem op1stg 6312

Description: Extract the first member of an ordered pair. (Contributed by NM, 19-Jul-2005.)

Assertion

Ref	Expression
op1stg	|- ( ( A e. V /\ B e. W ) -> ( 1st ` <. A , B >. ) = A )

Proof of Theorem op1stg

Dummy variables x y are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		opeq1 3862	. . . 4 |- ( x = A -> <. x , y >. = <. A , y >. )
2	1	fveq2d 5643	. . 3 |- ( x = A -> ( 1st ` <. x , y >. ) = ( 1st ` <. A , y >. ) )
3		id 19	. . 3 |- ( x = A -> x = A )
4	2, 3	eqeq12d 2246	. 2 |- ( x = A -> ( ( 1st ` <. x , y >. ) = x <-> ( 1st ` <. A , y >. ) = A ) )
5		opeq2 3863	. . . 4 |- ( y = B -> <. A , y >. = <. A , B >. )
6	5	fveq2d 5643	. . 3 |- ( y = B -> ( 1st ` <. A , y >. ) = ( 1st ` <. A , B >. ) )
7	6	eqeq1d 2240	. 2 |- ( y = B -> ( ( 1st ` <. A , y >. ) = A <-> ( 1st ` <. A , B >. ) = A ) )
8		vex 2805	. . 3 |- x e. _V
9		vex 2805	. . 3 |- y e. _V
10	8, 9	op1st 6308	. 2 |- ( 1st ` <. x , y >. ) = x
11	4, 7, 10	vtocl2g 2868	1 |- ( ( A e. V /\ B e. W ) -> ( 1st ` <. A , B >. ) = A )

Syntax hints:   -> wi 4   /\ wa 104   = wceq 1397   e. wcel 2202   <.cop 3672   ` cfv 5326   1stc1st 6300

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 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-13 2204  ax-14 2205  ax-ext 2213  ax-sep 4207  ax-pow 4264  ax-pr 4299  ax-un 4530

This theorem depends on definitions:  df-bi 117  df-3an 1006  df-tru 1400  df-nf 1509  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-ral 2515  df-rex 2516  df-v 2804  df-sbc 3032  df-un 3204  df-in 3206  df-ss 3213  df-pw 3654  df-sn 3675  df-pr 3676  df-op 3678  df-uni 3894  df-br 4089  df-opab 4151  df-mpt 4152  df-id 4390  df-xp 4731  df-rel 4732  df-cnv 4733  df-co 4734  df-dm 4735  df-rn 4736  df-iota 5286  df-fun 5328  df-fv 5334  df-1st 6302

This theorem is referenced by:  ot1stg  6314  ot2ndg  6315  1stconst  6385  algrflemg  6394  mpoxopn0yelv  6404  mpoxopoveq  6405  xpmapenlem  7034  1stinl  7272  1stinr  7274  mulpipq  7591  suplocexprlemlub  7943  aprcl  8825  frecuzrdgg  10677  swrdval  11228  qredeu  12668  qnumdenbi  12763  upxp  14995  uptx  14997  txmetcnp  15241  opvtxfv  15872