ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  sbceqg Unicode version

Theorem sbceqg 2947
Description: Distribute proper substitution through an equality relation. (Contributed by NM, 10-Nov-2005.) (Proof shortened by Andrew Salmon, 29-Jun-2011.)
Assertion
Ref Expression
sbceqg  |-  ( A  e.  V  ->  ( [. A  /  x ]. B  =  C  <->  [_ A  /  x ]_ B  =  [_ A  /  x ]_ C ) )

Proof of Theorem sbceqg
Dummy variables  y  z are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 dfsbcq2 2843 . . 3  |-  ( z  =  A  ->  ( [ z  /  x ] B  =  C  <->  [. A  /  x ]. B  =  C )
)
2 dfsbcq2 2843 . . . . 5  |-  ( z  =  A  ->  ( [ z  /  x ] y  e.  B  <->  [. A  /  x ]. y  e.  B )
)
32abbidv 2205 . . . 4  |-  ( z  =  A  ->  { y  |  [ z  /  x ] y  e.  B }  =  { y  |  [. A  /  x ]. y  e.  B } )
4 dfsbcq2 2843 . . . . 5  |-  ( z  =  A  ->  ( [ z  /  x ] y  e.  C  <->  [. A  /  x ]. y  e.  C )
)
54abbidv 2205 . . . 4  |-  ( z  =  A  ->  { y  |  [ z  /  x ] y  e.  C }  =  { y  |  [. A  /  x ]. y  e.  C } )
63, 5eqeq12d 2102 . . 3  |-  ( z  =  A  ->  ( { y  |  [
z  /  x ]
y  e.  B }  =  { y  |  [
z  /  x ]
y  e.  C }  <->  { y  |  [. A  /  x ]. y  e.  B }  =  {
y  |  [. A  /  x ]. y  e.  C } ) )
7 nfs1v 1863 . . . . . 6  |-  F/ x [ z  /  x ] y  e.  B
87nfab 2233 . . . . 5  |-  F/_ x { y  |  [
z  /  x ]
y  e.  B }
9 nfs1v 1863 . . . . . 6  |-  F/ x [ z  /  x ] y  e.  C
109nfab 2233 . . . . 5  |-  F/_ x { y  |  [
z  /  x ]
y  e.  C }
118, 10nfeq 2236 . . . 4  |-  F/ x { y  |  [
z  /  x ]
y  e.  B }  =  { y  |  [
z  /  x ]
y  e.  C }
12 sbab 2214 . . . . 5  |-  ( x  =  z  ->  B  =  { y  |  [
z  /  x ]
y  e.  B }
)
13 sbab 2214 . . . . 5  |-  ( x  =  z  ->  C  =  { y  |  [
z  /  x ]
y  e.  C }
)
1412, 13eqeq12d 2102 . . . 4  |-  ( x  =  z  ->  ( B  =  C  <->  { y  |  [ z  /  x ] y  e.  B }  =  { y  |  [ z  /  x ] y  e.  C } ) )
1511, 14sbie 1721 . . 3  |-  ( [ z  /  x ] B  =  C  <->  { y  |  [ z  /  x ] y  e.  B }  =  { y  |  [ z  /  x ] y  e.  C } )
161, 6, 15vtoclbg 2680 . 2  |-  ( A  e.  V  ->  ( [. A  /  x ]. B  =  C  <->  { y  |  [. A  /  x ]. y  e.  B }  =  {
y  |  [. A  /  x ]. y  e.  C } ) )
17 df-csb 2934 . . 3  |-  [_ A  /  x ]_ B  =  { y  |  [. A  /  x ]. y  e.  B }
18 df-csb 2934 . . 3  |-  [_ A  /  x ]_ C  =  { y  |  [. A  /  x ]. y  e.  C }
1917, 18eqeq12i 2101 . 2  |-  ( [_ A  /  x ]_ B  =  [_ A  /  x ]_ C  <->  { y  |  [. A  /  x ]. y  e.  B }  =  {
y  |  [. A  /  x ]. y  e.  C } )
2016, 19syl6bbr 196 1  |-  ( A  e.  V  ->  ( [. A  /  x ]. B  =  C  <->  [_ A  /  x ]_ B  =  [_ A  /  x ]_ C ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 103    = wceq 1289    e. wcel 1438   [wsb 1692   {cab 2074   [.wsbc 2840   [_csb 2933
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-io 665  ax-5 1381  ax-7 1382  ax-gen 1383  ax-ie1 1427  ax-ie2 1428  ax-8 1440  ax-10 1441  ax-11 1442  ax-i12 1443  ax-bndl 1444  ax-4 1445  ax-17 1464  ax-i9 1468  ax-ial 1472  ax-i5r 1473  ax-ext 2070
This theorem depends on definitions:  df-bi 115  df-tru 1292  df-nf 1395  df-sb 1693  df-clab 2075  df-cleq 2081  df-clel 2084  df-nfc 2217  df-v 2621  df-sbc 2841  df-csb 2934
This theorem is referenced by:  sbcne12g  2949  sbceq1g  2951  sbceq2g  2953  sbcfng  5159
  Copyright terms: Public domain W3C validator