Theorem rneqdmfinf1o 9217

Description: Any function from a finite set onto the same set must be a bijection. (Contributed by AV, 5-Jul-2021.)

Assertion

Ref	Expression
rneqdmfinf1o	⊢ ((𝐴 ∈ Fin ∧ 𝐹 Fn 𝐴 ∧ ran 𝐹 = 𝐴) → 𝐹:𝐴–1-1-onto→𝐴)

Proof of Theorem rneqdmfinf1o

Step	Hyp	Ref	Expression
1		dffn4 6741	. . . . 5 ⊢ (𝐹 Fn 𝐴 ↔ 𝐹:𝐴–onto→ran 𝐹)
2	1	biimpi 216	. . . 4 ⊢ (𝐹 Fn 𝐴 → 𝐹:𝐴–onto→ran 𝐹)
3	2	3ad2ant2 1134	. . 3 ⊢ ((𝐴 ∈ Fin ∧ 𝐹 Fn 𝐴 ∧ ran 𝐹 = 𝐴) → 𝐹:𝐴–onto→ran 𝐹)
4		foeq3 6733	. . . 4 ⊢ (ran 𝐹 = 𝐴 → (𝐹:𝐴–onto→ran 𝐹 ↔ 𝐹:𝐴–onto→𝐴))
5	4	3ad2ant3 1135	. . 3 ⊢ ((𝐴 ∈ Fin ∧ 𝐹 Fn 𝐴 ∧ ran 𝐹 = 𝐴) → (𝐹:𝐴–onto→ran 𝐹 ↔ 𝐹:𝐴–onto→𝐴))
6	3, 5	mpbid 232	. 2 ⊢ ((𝐴 ∈ Fin ∧ 𝐹 Fn 𝐴 ∧ ran 𝐹 = 𝐴) → 𝐹:𝐴–onto→𝐴)
7		enrefg 8906	. . 3 ⊢ (𝐴 ∈ Fin → 𝐴 ≈ 𝐴)
8	7	3ad2ant1 1133	. 2 ⊢ ((𝐴 ∈ Fin ∧ 𝐹 Fn 𝐴 ∧ ran 𝐹 = 𝐴) → 𝐴 ≈ 𝐴)
9		simp1 1136	. 2 ⊢ ((𝐴 ∈ Fin ∧ 𝐹 Fn 𝐴 ∧ ran 𝐹 = 𝐴) → 𝐴 ∈ Fin)
10		fofinf1o 9216	. 2 ⊢ ((𝐹:𝐴–onto→𝐴 ∧ 𝐴 ≈ 𝐴 ∧ 𝐴 ∈ Fin) → 𝐹:𝐴–1-1-onto→𝐴)
11	6, 8, 9, 10	syl3anc 1373	1 ⊢ ((𝐴 ∈ Fin ∧ 𝐹 Fn 𝐴 ∧ ran 𝐹 = 𝐴) → 𝐹:𝐴–1-1-onto→𝐴)

Syntax hints:   → wi 4   ↔ wb 206   ∧ w3a 1086   = wceq 1541   ∈ wcel 2111   class class class wbr 5089  ran crn 5615   Fn wfn 6476  –onto→wfo 6479  –1-1-onto→wf1o 6480   ≈ cen 8866  Fincfn 8869

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-10 2144  ax-11 2160  ax-12 2180  ax-ext 2703  ax-sep 5232  ax-nul 5242  ax-pow 5301  ax-pr 5368  ax-un 7668

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3or 1087  df-3an 1088  df-tru 1544  df-fal 1554  df-ex 1781  df-nf 1785  df-sb 2068  df-mo 2535  df-eu 2564  df-clab 2710  df-cleq 2723  df-clel 2806  df-nfc 2881  df-ne 2929  df-ral 3048  df-rex 3057  df-reu 3347  df-rab 3396  df-v 3438  df-sbc 3737  df-csb 3846  df-dif 3900  df-un 3902  df-in 3904  df-ss 3914  df-pss 3917  df-nul 4281  df-if 4473  df-pw 4549  df-sn 4574  df-pr 4576  df-op 4580  df-uni 4857  df-br 5090  df-opab 5152  df-mpt 5171  df-tr 5197  df-id 5509  df-eprel 5514  df-po 5522  df-so 5523  df-fr 5567  df-we 5569  df-xp 5620  df-rel 5621  df-cnv 5622  df-co 5623  df-dm 5624  df-rn 5625  df-res 5626  df-ima 5627  df-ord 6309  df-on 6310  df-lim 6311  df-suc 6312  df-iota 6437  df-fun 6483  df-fn 6484  df-f 6485  df-f1 6486  df-fo 6487  df-f1o 6488  df-fv 6489  df-om 7797  df-1o 8385  df-er 8622  df-en 8870  df-dom 8871  df-sdom 8872  df-fin 8873

This theorem is referenced by:  gausslemma2dlem1  27304