Theorem f1eq2 5324

Description: Equality theorem for one-to-one functions. (Contributed by NM, 10-Feb-1997.)

Assertion

Ref	Expression
f1eq2	⊢ (𝐴 = 𝐵 → (𝐹:𝐴–1-1→𝐶 ↔ 𝐹:𝐵–1-1→𝐶))

Proof of Theorem f1eq2

Step	Hyp	Ref	Expression
1		feq2 5256	. . 3 ⊢ (𝐴 = 𝐵 → (𝐹:𝐴⟶𝐶 ↔ 𝐹:𝐵⟶𝐶))
2	1	anbi1d 460	. 2 ⊢ (𝐴 = 𝐵 → ((𝐹:𝐴⟶𝐶 ∧ Fun ◡𝐹) ↔ (𝐹:𝐵⟶𝐶 ∧ Fun ◡𝐹)))
3		df-f1 5128	. 2 ⊢ (𝐹:𝐴–1-1→𝐶 ↔ (𝐹:𝐴⟶𝐶 ∧ Fun ◡𝐹))
4		df-f1 5128	. 2 ⊢ (𝐹:𝐵–1-1→𝐶 ↔ (𝐹:𝐵⟶𝐶 ∧ Fun ◡𝐹))
5	2, 3, 4	3bitr4g 222	1 ⊢ (𝐴 = 𝐵 → (𝐹:𝐴–1-1→𝐶 ↔ 𝐹:𝐵–1-1→𝐶))

Syntax hints:   → wi 4   ∧ wa 103   ↔ wb 104   = wceq 1331  ^◡ccnv 4538  Fun wfun 5117  ⟶wf 5119  –1-1→wf1 5120

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-5 1423  ax-gen 1425  ax-4 1487  ax-17 1506  ax-ext 2121

This theorem depends on definitions:  df-bi 116  df-cleq 2132  df-fn 5126  df-f 5127  df-f1 5128

This theorem is referenced by:  f1oeq2  5357  f1eq123d  5360  brdomg  6642  ennnfonelemen  11934