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

Theorem infeq1 6976
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 6951 . 2  |-  ( B  =  C  ->  sup ( B ,  A ,  `' R )  =  sup ( C ,  A ,  `' R ) )
2 df-inf 6950 . 2  |- inf ( B ,  A ,  R
)  =  sup ( B ,  A ,  `' R )
3 df-inf 6950 . 2  |- inf ( C ,  A ,  R
)  =  sup ( C ,  A ,  `' R )
41, 2, 33eqtr4g 2224 1  |-  ( B  =  C  -> inf ( B ,  A ,  R
)  = inf ( C ,  A ,  R
) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    = wceq 1343   `'ccnv 4603   supcsup 6947  infcinf 6948
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147
This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-ral 2449  df-rex 2450  df-rab 2453  df-uni 3790  df-sup 6949  df-inf 6950
This theorem is referenced by:  infeq1d  6977  infeq1i  6978
  Copyright terms: Public domain W3C validator