MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  f1stres Unicode version

Theorem f1stres 6300
Description: Mapping of a restriction of the  1st (first member of an ordered pair) function. (Contributed by NM, 11-Oct-2004.) (Revised by Mario Carneiro, 8-Sep-2013.)
Assertion
Ref Expression
f1stres  |-  ( 1st  |`  ( A  X.  B
) ) : ( A  X.  B ) --> A

Proof of Theorem f1stres
Dummy variables  x  y  z are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 vex 2895 . . . . . . . 8  |-  y  e. 
_V
2 vex 2895 . . . . . . . 8  |-  z  e. 
_V
31, 2op1sta 5284 . . . . . . 7  |-  U. dom  {
<. y ,  z >. }  =  y
43eleq1i 2443 . . . . . 6  |-  ( U. dom  { <. y ,  z
>. }  e.  A  <->  y  e.  A )
54biimpri 198 . . . . 5  |-  ( y  e.  A  ->  U. dom  {
<. y ,  z >. }  e.  A )
65adantr 452 . . . 4  |-  ( ( y  e.  A  /\  z  e.  B )  ->  U. dom  { <. y ,  z >. }  e.  A )
76rgen2 2738 . . 3  |-  A. y  e.  A  A. z  e.  B  U. dom  { <. y ,  z >. }  e.  A
8 sneq 3761 . . . . . . 7  |-  ( x  =  <. y ,  z
>.  ->  { x }  =  { <. y ,  z
>. } )
98dmeqd 5005 . . . . . 6  |-  ( x  =  <. y ,  z
>.  ->  dom  { x }  =  dom  { <. y ,  z >. } )
109unieqd 3961 . . . . 5  |-  ( x  =  <. y ,  z
>.  ->  U. dom  { x }  =  U. dom  { <. y ,  z >. } )
1110eleq1d 2446 . . . 4  |-  ( x  =  <. y ,  z
>.  ->  ( U. dom  { x }  e.  A  <->  U.
dom  { <. y ,  z
>. }  e.  A ) )
1211ralxp 4949 . . 3  |-  ( A. x  e.  ( A  X.  B ) U. dom  { x }  e.  A  <->  A. y  e.  A  A. z  e.  B  U. dom  { <. y ,  z
>. }  e.  A )
137, 12mpbir 201 . 2  |-  A. x  e.  ( A  X.  B
) U. dom  {
x }  e.  A
14 df-1st 6281 . . . . 5  |-  1st  =  ( x  e.  _V  |->  U.
dom  { x } )
1514reseq1i 5075 . . . 4  |-  ( 1st  |`  ( A  X.  B
) )  =  ( ( x  e.  _V  |->  U.
dom  { x } )  |`  ( A  X.  B
) )
16 ssv 3304 . . . . 5  |-  ( A  X.  B )  C_  _V
17 resmpt 5124 . . . . 5  |-  ( ( A  X.  B ) 
C_  _V  ->  ( ( x  e.  _V  |->  U.
dom  { x } )  |`  ( A  X.  B
) )  =  ( x  e.  ( A  X.  B )  |->  U.
dom  { x } ) )
1816, 17ax-mp 8 . . . 4  |-  ( ( x  e.  _V  |->  U.
dom  { x } )  |`  ( A  X.  B
) )  =  ( x  e.  ( A  X.  B )  |->  U.
dom  { x } )
1915, 18eqtri 2400 . . 3  |-  ( 1st  |`  ( A  X.  B
) )  =  ( x  e.  ( A  X.  B )  |->  U.
dom  { x } )
2019fmpt 5822 . 2  |-  ( A. x  e.  ( A  X.  B ) U. dom  { x }  e.  A  <->  ( 1st  |`  ( A  X.  B ) ) : ( A  X.  B
) --> A )
2113, 20mpbi 200 1  |-  ( 1st  |`  ( A  X.  B
) ) : ( A  X.  B ) --> A
Colors of variables: wff set class
Syntax hints:    = wceq 1649    e. wcel 1717   A.wral 2642   _Vcvv 2892    C_ wss 3256   {csn 3750   <.cop 3753   U.cuni 3950    e. cmpt 4200    X. cxp 4809   dom cdm 4811    |` cres 4813   -->wf 5383   1stc1st 6279
This theorem is referenced by:  fo1stres  6302  1stcof  6306  fparlem1  6378  domssex2  7196  domssex  7197  unxpwdom2  7482  1stfcl  14214  tx1cn  17555  xpinpreima  24101  xpinpreima2  24102  1stmbfm  24397  hausgraph  27193
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-3 7  ax-mp 8  ax-gen 1552  ax-5 1563  ax-17 1623  ax-9 1661  ax-8 1682  ax-14 1721  ax-6 1736  ax-7 1741  ax-11 1753  ax-12 1939  ax-ext 2361  ax-sep 4264  ax-nul 4272  ax-pr 4337
This theorem depends on definitions:  df-bi 178  df-or 360  df-an 361  df-3an 938  df-tru 1325  df-ex 1548  df-nf 1551  df-sb 1656  df-eu 2235  df-mo 2236  df-clab 2367  df-cleq 2373  df-clel 2376  df-nfc 2505  df-ne 2545  df-ral 2647  df-rex 2648  df-rab 2651  df-v 2894  df-sbc 3098  df-csb 3188  df-dif 3259  df-un 3261  df-in 3263  df-ss 3270  df-nul 3565  df-if 3676  df-sn 3756  df-pr 3757  df-op 3759  df-uni 3951  df-iun 4030  df-br 4147  df-opab 4201  df-mpt 4202  df-id 4432  df-xp 4817  df-rel 4818  df-cnv 4819  df-co 4820  df-dm 4821  df-rn 4822  df-res 4823  df-ima 4824  df-iota 5351  df-fun 5389  df-fn 5390  df-f 5391  df-fv 5395  df-1st 6281
  Copyright terms: Public domain W3C validator