Theorem rnco 6235

Description: The range of the composition of two classes. (Contributed by NM, 12-Dec-2006.) (Proof shortened by Peter Mazsa, 2-Oct-2022.) Avoid ax-11 2190. (Revised by TM, 24-Jan-2026.)

Assertion

Ref	Expression
rnco	⊢ ran (𝐴 ∘ 𝐵) = ran (𝐴 ↾ ran 𝐵)

Proof of Theorem rnco

Dummy variables 𝑥 𝑤 𝑦 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		vex 3457	. . . . . 6 ⊢ 𝑥 ∈ V
2		vex 3457	. . . . . 6 ⊢ 𝑦 ∈ V
3	1, 2	brco 5840	. . . . 5 ⊢ (𝑥(𝐴 ∘ 𝐵)𝑦 ↔ ∃𝑧(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦))
4	3	exbii 1867	. . . 4 ⊢ (∃𝑥 𝑥(𝐴 ∘ 𝐵)𝑦 ↔ ∃𝑥∃𝑧(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦))
5		breq1 5102	. . . . . 6 ⊢ (𝑥 = 𝑤 → (𝑥𝐵𝑧 ↔ 𝑤𝐵𝑧))
6	5	anbi1d 640	. . . . 5 ⊢ (𝑥 = 𝑤 → ((𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦) ↔ (𝑤𝐵𝑧 ∧ 𝑧𝐴𝑦)))
7		breq2 5103	. . . . . 6 ⊢ (𝑧 = 𝑤 → (𝑥𝐵𝑧 ↔ 𝑥𝐵𝑤))
8		breq1 5102	. . . . . 6 ⊢ (𝑧 = 𝑤 → (𝑧𝐴𝑦 ↔ 𝑤𝐴𝑦))
9	7, 8	anbi12d 641	. . . . 5 ⊢ (𝑧 = 𝑤 → ((𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦) ↔ (𝑥𝐵𝑤 ∧ 𝑤𝐴𝑦)))
10	6, 9	excomw 2065	. . . 4 ⊢ (∃𝑥∃𝑧(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦) ↔ ∃𝑧∃𝑥(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦))
11		vex 3457	. . . . . . . 8 ⊢ 𝑧 ∈ V
12	11	elrn 5867	. . . . . . 7 ⊢ (𝑧 ∈ ran 𝐵 ↔ ∃𝑥 𝑥𝐵𝑧)
13	12	anbi1i 633	. . . . . 6 ⊢ ((𝑧 ∈ ran 𝐵 ∧ 𝑧𝐴𝑦) ↔ (∃𝑥 𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦))
14	2	brresi 5972	. . . . . 6 ⊢ (𝑧(𝐴 ↾ ran 𝐵)𝑦 ↔ (𝑧 ∈ ran 𝐵 ∧ 𝑧𝐴𝑦))
15		19.41v 1968	. . . . . 6 ⊢ (∃𝑥(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦) ↔ (∃𝑥 𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦))
16	13, 14, 15	3bitr4ri 306	. . . . 5 ⊢ (∃𝑥(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦) ↔ 𝑧(𝐴 ↾ ran 𝐵)𝑦)
17	16	exbii 1867	. . . 4 ⊢ (∃𝑧∃𝑥(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦) ↔ ∃𝑧 𝑧(𝐴 ↾ ran 𝐵)𝑦)
18	4, 10, 17	3bitri 299	. . 3 ⊢ (∃𝑥 𝑥(𝐴 ∘ 𝐵)𝑦 ↔ ∃𝑧 𝑧(𝐴 ↾ ran 𝐵)𝑦)
19	2	elrn 5867	. . 3 ⊢ (𝑦 ∈ ran (𝐴 ∘ 𝐵) ↔ ∃𝑥 𝑥(𝐴 ∘ 𝐵)𝑦)
20	2	elrn 5867	. . 3 ⊢ (𝑦 ∈ ran (𝐴 ↾ ran 𝐵) ↔ ∃𝑧 𝑧(𝐴 ↾ ran 𝐵)𝑦)
21	18, 19, 20	3bitr4i 305	. 2 ⊢ (𝑦 ∈ ran (𝐴 ∘ 𝐵) ↔ 𝑦 ∈ ran (𝐴 ↾ ran 𝐵))
22	21	eqriv 2758	1 ⊢ ran (𝐴 ∘ 𝐵) = ran (𝐴 ↾ ran 𝐵)

Syntax hints:   ∧ wa 399   = wceq 1559  ∃wex 1798   ∈ wcel 2141   class class class wbr 5099  ran crn 5646   ↾ cres 5647   ∘ ccom 5649

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1814  ax-4 1828  ax-5 1929  ax-6 1986  ax-7 2027  ax-8 2143  ax-9 2151  ax-ext 2733  ax-sep 5245  ax-pr 5389

This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-3an 1099  df-tru 1562  df-fal 1572  df-ex 1799  df-sb 2090  df-clab 2740  df-cleq 2753  df-clel 2836  df-ral 3076  df-rex 3086  df-rab 3414  df-v 3455  df-dif 3907  df-un 3909  df-in 3911  df-ss 3921  df-nul 4286  df-if 4480  df-sn 4582  df-pr 4584  df-op 4588  df-br 5100  df-opab 5162  df-xp 5651  df-cnv 5653  df-co 5654  df-dm 5655  df-rn 5656  df-res 5657

This theorem is referenced by:  rnco2  6237  coeq0  6239  focofo  6787  cofunexg  7926  1stcof  7996  2ndcof  7997  smobeth  10541  cycpmconjv  33283  elmsubrn  35842  ftc1anclem3  38158