ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  f1eq2 GIF version

Theorem f1eq2 5526
Description: Equality theorem for one-to-one functions. (Contributed by NM, 10-Feb-1997.)
Assertion
Ref Expression
f1eq2 (𝐴 = 𝐵 → (𝐹:𝐴1-1𝐶𝐹:𝐵1-1𝐶))

Proof of Theorem f1eq2
StepHypRef Expression
1 feq2 5456 . . 3 (𝐴 = 𝐵 → (𝐹:𝐴𝐶𝐹:𝐵𝐶))
21anbi1d 465 . 2 (𝐴 = 𝐵 → ((𝐹:𝐴𝐶 ∧ Fun 𝐹) ↔ (𝐹:𝐵𝐶 ∧ Fun 𝐹)))
3 df-f1 5322 . 2 (𝐹:𝐴1-1𝐶 ↔ (𝐹:𝐴𝐶 ∧ Fun 𝐹))
4 df-f1 5322 . 2 (𝐹:𝐵1-1𝐶 ↔ (𝐹:𝐵𝐶 ∧ Fun 𝐹))
52, 3, 43bitr4g 223 1 (𝐴 = 𝐵 → (𝐹:𝐴1-1𝐶𝐹:𝐵1-1𝐶))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 104  wb 105   = wceq 1395  ccnv 4717  Fun wfun 5311  wf 5313  1-1wf1 5314
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-5 1493  ax-gen 1495  ax-4 1556  ax-17 1572  ax-ext 2211
This theorem depends on definitions:  df-bi 117  df-cleq 2222  df-fn 5320  df-f 5321  df-f1 5322
This theorem is referenced by:  f1oeq2  5560  f1eq123d  5563  f10d  5606  brdom2g  6894  brdomg  6895  ennnfonelemen  12987  ausgrusgrben  15960  dom1o  16314
  Copyright terms: Public domain W3C validator