Theorem f1resf1 6727

Description: The restriction of an injective function is injective. (Contributed by AV, 28-Jun-2022.)

Assertion

Ref	Expression
f1resf1	⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝐶 ⊆ 𝐴 ∧ (𝐹 ↾ 𝐶):𝐶⟶𝐷) → (𝐹 ↾ 𝐶):𝐶–1-1→𝐷)

Proof of Theorem f1resf1

Step	Hyp	Ref	Expression
1		f1ssres 6726	. . 3 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝐶 ⊆ 𝐴) → (𝐹 ↾ 𝐶):𝐶–1-1→𝐵)
2	1	3adant3 1132	. 2 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝐶 ⊆ 𝐴 ∧ (𝐹 ↾ 𝐶):𝐶⟶𝐷) → (𝐹 ↾ 𝐶):𝐶–1-1→𝐵)
3		frn 6658	. . 3 ⊢ ((𝐹 ↾ 𝐶):𝐶⟶𝐷 → ran (𝐹 ↾ 𝐶) ⊆ 𝐷)
4	3	3ad2ant3 1135	. 2 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝐶 ⊆ 𝐴 ∧ (𝐹 ↾ 𝐶):𝐶⟶𝐷) → ran (𝐹 ↾ 𝐶) ⊆ 𝐷)
5		f1ssr 6725	. 2 ⊢ (((𝐹 ↾ 𝐶):𝐶–1-1→𝐵 ∧ ran (𝐹 ↾ 𝐶) ⊆ 𝐷) → (𝐹 ↾ 𝐶):𝐶–1-1→𝐷)
6	2, 4, 5	syl2anc 584	1 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝐶 ⊆ 𝐴 ∧ (𝐹 ↾ 𝐶):𝐶⟶𝐷) → (𝐹 ↾ 𝐶):𝐶–1-1→𝐷)

Syntax hints:   → wi 4   ∧ w3a 1086   ⊆ wss 3902  ran crn 5617   ↾ cres 5618  ⟶wf 6477  –1-1→wf1 6478

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1968  ax-7 2009  ax-8 2113  ax-9 2121  ax-ext 2703  ax-sep 5234  ax-nul 5244  ax-pr 5370

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1544  df-fal 1554  df-ex 1781  df-sb 2068  df-clab 2710  df-cleq 2723  df-clel 2806  df-ral 3048  df-rex 3057  df-rab 3396  df-v 3438  df-dif 3905  df-un 3907  df-in 3909  df-ss 3919  df-nul 4284  df-if 4476  df-sn 4577  df-pr 4579  df-op 4583  df-br 5092  df-opab 5154  df-xp 5622  df-rel 5623  df-cnv 5624  df-co 5625  df-dm 5626  df-rn 5627  df-res 5628  df-fun 6483  df-fn 6484  df-f 6485  df-f1 6486

This theorem is referenced by:  inlresf1  9805  inrresf1  9807  pfxf1  32918  aks6d1c2  42162  3f1oss1  47105