ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  infeq1 Unicode version

Theorem infeq1 7178
Description: Equality theorem for infimum. (Contributed by AV, 2-Sep-2020.)
Assertion
Ref Expression
infeq1  |-  ( B  =  C  -> inf ( B ,  A ,  R
)  = inf ( C ,  A ,  R
) )

Proof of Theorem infeq1
StepHypRef Expression
1 supeq1 7153 . 2  |-  ( B  =  C  ->  sup ( B ,  A ,  `' R )  =  sup ( C ,  A ,  `' R ) )
2 df-inf 7152 . 2  |- inf ( B ,  A ,  R
)  =  sup ( B ,  A ,  `' R )
3 df-inf 7152 . 2  |- inf ( C ,  A ,  R
)  =  sup ( C ,  A ,  `' R )
41, 2, 33eqtr4g 2287 1  |-  ( B  =  C  -> inf ( B ,  A ,  R
)  = inf ( C ,  A ,  R
) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    = wceq 1395   `'ccnv 4718   supcsup 7149  infcinf 7150
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 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-ext 2211
This theorem depends on definitions:  df-bi 117  df-tru 1398  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ral 2513  df-rex 2514  df-rab 2517  df-uni 3889  df-sup 7151  df-inf 7152
This theorem is referenced by:  infeq1d  7179  infeq1i  7180
  Copyright terms: Public domain W3C validator