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Theorem f1eq2 5594
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 5517 . . 3 (𝐴 = 𝐵 → (𝐹:𝐴𝐶𝐹:𝐵𝐶))
21anbi1d 469 . 2 (𝐴 = 𝐵 → ((𝐹:𝐴𝐶 ∧ Fun 𝐹) ↔ (𝐹:𝐵𝐶 ∧ Fun 𝐹)))
3 df-f1 5382 . 2 (𝐹:𝐴1-1𝐶 ↔ (𝐹:𝐴𝐶 ∧ Fun 𝐹))
4 df-f1 5382 . 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
This proof depends on syntax axioms:  wi 4  wa 104  wb 105   = wceq 1402  ccnv 4773  Fun wfun 5371  wf 5373  1-1wf1 5374
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1500  ax-gen 1502  ax-4 1563  ax-17 1579  ax-ext 2220
This proof depends on definitions:  df-bi 117  df-cleq 2231  df-fn 5380  df-f 5381  df-f1 5382
This theorem is used by:  f1oeq2  5628  f1eq123d  5631  f10d  5675  brdom2g  7031  brdomg  7032  dom1o  7116  hashf1  11287  ennnfonelemen  13312  ausgrusgrben  16409  usgr0  16480  uspgr1edc  16481
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