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Theorem f1eq2 5436
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 5368 . . 3 (𝐴 = 𝐵 → (𝐹:𝐴𝐶𝐹:𝐵𝐶))
21anbi1d 465 . 2 (𝐴 = 𝐵 → ((𝐹:𝐴𝐶 ∧ Fun 𝐹) ↔ (𝐹:𝐵𝐶 ∧ Fun 𝐹)))
3 df-f1 5240 . 2 (𝐹:𝐴1-1𝐶 ↔ (𝐹:𝐴𝐶 ∧ Fun 𝐹))
4 df-f1 5240 . 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 1364  ccnv 4643  Fun wfun 5229  wf 5231  1-1wf1 5232
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 1458  ax-gen 1460  ax-4 1521  ax-17 1537  ax-ext 2171
This theorem depends on definitions:  df-bi 117  df-cleq 2182  df-fn 5238  df-f 5239  df-f1 5240
This theorem is referenced by:  f1oeq2  5469  f1eq123d  5472  brdomg  6775  ennnfonelemen  12475
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