ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  fneq2 GIF version

Theorem fneq2 5410
Description: Equality theorem for function predicate with domain. (Contributed by NM, 1-Aug-1994.)
Assertion
Ref Expression
fneq2 (𝐴 = 𝐵 → (𝐹 Fn 𝐴𝐹 Fn 𝐵))

Proof of Theorem fneq2
StepHypRef Expression
1 eqeq2 2239 . . 3 (𝐴 = 𝐵 → (dom 𝐹 = 𝐴 ↔ dom 𝐹 = 𝐵))
21anbi2d 464 . 2 (𝐴 = 𝐵 → ((Fun 𝐹 ∧ dom 𝐹 = 𝐴) ↔ (Fun 𝐹 ∧ dom 𝐹 = 𝐵)))
3 df-fn 5321 . 2 (𝐹 Fn 𝐴 ↔ (Fun 𝐹 ∧ dom 𝐹 = 𝐴))
4 df-fn 5321 . 2 (𝐹 Fn 𝐵 ↔ (Fun 𝐹 ∧ dom 𝐹 = 𝐵))
52, 3, 43bitr4g 223 1 (𝐴 = 𝐵 → (𝐹 Fn 𝐴𝐹 Fn 𝐵))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 104  wb 105   = wceq 1395  dom cdm 4719  Fun wfun 5312   Fn wfn 5313
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 5321
This theorem is referenced by:  fneq2d  5412  fneq2i  5416  feq2  5457  foeq2  5547  f1o00  5610  eqfnfv2  5735  tfr0dm  6474  tfrlemisucaccv  6477  tfrlemi1  6484  tfrlemi14d  6485  tfrexlem  6486  tfr1onlemsucfn  6492  tfr1onlemsucaccv  6493  tfr1onlembxssdm  6495  tfr1onlembfn  6496  tfr1onlemaccex  6500  tfr1onlemres  6501  ixpeq1  6864  0fz1  10253
  Copyright terms: Public domain W3C validator