Theorem fmpocos 42800

Description: Composition of two functions. Variation of fmpoco 8062 with more context in the substitution hypothesis for 𝑇. (Contributed by SN, 14-Mar-2025.)

Hypotheses

Ref	Expression
fmpocos.1	⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → 𝑅 ∈ 𝐶)
fmpocos.2	⊢ (𝜑 → 𝐹 = (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑅))
fmpocos.3	⊢ (𝜑 → 𝐺 = (𝑧 ∈ 𝐶 ↦ 𝑆))
fmpocos.4	⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → ⦋𝑅 / 𝑧⦌𝑆 = 𝑇)

Assertion

Ref	Expression
fmpocos	⊢ (𝜑 → (𝐺 ∘ 𝐹) = (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑇))

Distinct variable groups:   𝑥,𝑦,𝐵   𝑥,𝑧,𝐶,𝑦   𝜑,𝑥,𝑦   𝑥,𝑆,𝑦   𝑥,𝐴,𝑦   𝑧,𝑅   𝑧,𝑇

Allowed substitution hints:   𝜑(𝑧)   𝐴(𝑧)   𝐵(𝑧)   𝑅(𝑥,𝑦)   𝑆(𝑧)   𝑇(𝑥,𝑦)   𝐹(𝑥,𝑦,𝑧)   𝐺(𝑥,𝑦,𝑧)

Proof of Theorem fmpocos

Dummy variables 𝑣 𝑢 𝑤 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		fmpocos.1	. . . . . 6 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → 𝑅 ∈ 𝐶)
2	1	ralrimivva 3199	. . . . 5 ⊢ (𝜑 → ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝑅 ∈ 𝐶)
3		eqid 2756	. . . . . 6 ⊢ (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑅) = (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑅)
4	3	fmpo 8038	. . . . 5 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝑅 ∈ 𝐶 ↔ (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑅):(𝐴 × 𝐵)⟶𝐶)
5	2, 4	sylib 220	. . . 4 ⊢ (𝜑 → (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑅):(𝐴 × 𝐵)⟶𝐶)
6		nfcv 2918	. . . . . . 7 ⊢ Ⅎ𝑢𝑅
7		nfcv 2918	. . . . . . 7 ⊢ Ⅎ𝑣𝑅
8		nfcv 2918	. . . . . . . 8 ⊢ Ⅎ𝑥𝑣
9		nfcsb1v 3871	. . . . . . . 8 ⊢ Ⅎ𝑥⦋𝑢 / 𝑥⦌𝑅
10	8, 9	nfcsbw 3873	. . . . . . 7 ⊢ Ⅎ𝑥⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅
11		nfcsb1v 3871	. . . . . . 7 ⊢ Ⅎ𝑦⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅
12		csbeq1a 3861	. . . . . . . 8 ⊢ (𝑥 = 𝑢 → 𝑅 = ⦋𝑢 / 𝑥⦌𝑅)
13		csbeq1a 3861	. . . . . . . 8 ⊢ (𝑦 = 𝑣 → ⦋𝑢 / 𝑥⦌𝑅 = ⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅)
14	12, 13	sylan9eq 2811	. . . . . . 7 ⊢ ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → 𝑅 = ⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅)
15	6, 7, 10, 11, 14	cbvmpo 7479	. . . . . 6 ⊢ (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑅) = (𝑢 ∈ 𝐴, 𝑣 ∈ 𝐵 ↦ ⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅)
16		vex 3452	. . . . . . . . 9 ⊢ 𝑢 ∈ V
17		vex 3452	. . . . . . . . 9 ⊢ 𝑣 ∈ V
18	16, 17	op2ndd 7970	. . . . . . . 8 ⊢ (𝑤 = ⟨𝑢, 𝑣⟩ → (2nd ‘𝑤) = 𝑣)
19	16, 17	op1std 7969	. . . . . . . . 9 ⊢ (𝑤 = ⟨𝑢, 𝑣⟩ → (1st ‘𝑤) = 𝑢)
20	19	csbeq1d 3851	. . . . . . . 8 ⊢ (𝑤 = ⟨𝑢, 𝑣⟩ → ⦋(1st ‘𝑤) / 𝑥⦌𝑅 = ⦋𝑢 / 𝑥⦌𝑅)
21	18, 20	csbeq12dv 3856	. . . . . . 7 ⊢ (𝑤 = ⟨𝑢, 𝑣⟩ → ⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅 = ⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅)
22	21	mpompt 7499	. . . . . 6 ⊢ (𝑤 ∈ (𝐴 × 𝐵) ↦ ⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅) = (𝑢 ∈ 𝐴, 𝑣 ∈ 𝐵 ↦ ⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅)
23	15, 22	eqtr4i 2782	. . . . 5 ⊢ (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑅) = (𝑤 ∈ (𝐴 × 𝐵) ↦ ⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅)
24	23	fmpt 7080	. . . 4 ⊢ (∀𝑤 ∈ (𝐴 × 𝐵)⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅 ∈ 𝐶 ↔ (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑅):(𝐴 × 𝐵)⟶𝐶)
25	5, 24	sylibr 236	. . 3 ⊢ (𝜑 → ∀𝑤 ∈ (𝐴 × 𝐵)⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅 ∈ 𝐶)
26		fmpocos.2	. . . 4 ⊢ (𝜑 → 𝐹 = (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑅))
27	26, 23	eqtrdi 2807	. . 3 ⊢ (𝜑 → 𝐹 = (𝑤 ∈ (𝐴 × 𝐵) ↦ ⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅))
28		fmpocos.3	. . 3 ⊢ (𝜑 → 𝐺 = (𝑧 ∈ 𝐶 ↦ 𝑆))
29	25, 27, 28	fmptcos 7102	. 2 ⊢ (𝜑 → (𝐺 ∘ 𝐹) = (𝑤 ∈ (𝐴 × 𝐵) ↦ ⦋⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅 / 𝑧⦌𝑆))
30	21	csbeq1d 3851	. . . . 5 ⊢ (𝑤 = ⟨𝑢, 𝑣⟩ → ⦋⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅 / 𝑧⦌𝑆 = ⦋⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅 / 𝑧⦌𝑆)
31	30	mpompt 7499	. . . 4 ⊢ (𝑤 ∈ (𝐴 × 𝐵) ↦ ⦋⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅 / 𝑧⦌𝑆) = (𝑢 ∈ 𝐴, 𝑣 ∈ 𝐵 ↦ ⦋⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅 / 𝑧⦌𝑆)
32		nfcv 2918	. . . . 5 ⊢ Ⅎ𝑢⦋𝑅 / 𝑧⦌𝑆
33		nfcv 2918	. . . . 5 ⊢ Ⅎ𝑣⦋𝑅 / 𝑧⦌𝑆
34		nfcv 2918	. . . . . 6 ⊢ Ⅎ𝑥𝑆
35	10, 34	nfcsbw 3873	. . . . 5 ⊢ Ⅎ𝑥⦋⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅 / 𝑧⦌𝑆
36		nfcv 2918	. . . . . 6 ⊢ Ⅎ𝑦𝑆
37	11, 36	nfcsbw 3873	. . . . 5 ⊢ Ⅎ𝑦⦋⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅 / 𝑧⦌𝑆
38	14	csbeq1d 3851	. . . . 5 ⊢ ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ⦋𝑅 / 𝑧⦌𝑆 = ⦋⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅 / 𝑧⦌𝑆)
39	32, 33, 35, 37, 38	cbvmpo 7479	. . . 4 ⊢ (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ ⦋𝑅 / 𝑧⦌𝑆) = (𝑢 ∈ 𝐴, 𝑣 ∈ 𝐵 ↦ ⦋⦋𝑣 / 𝑦⦌⦋𝑢 / 𝑥⦌𝑅 / 𝑧⦌𝑆)
40	31, 39	eqtr4i 2782	. . 3 ⊢ (𝑤 ∈ (𝐴 × 𝐵) ↦ ⦋⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅 / 𝑧⦌𝑆) = (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ ⦋𝑅 / 𝑧⦌𝑆)
41		fmpocos.4	. . . . 5 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → ⦋𝑅 / 𝑧⦌𝑆 = 𝑇)
42	41	3impb 1123	. . . 4 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → ⦋𝑅 / 𝑧⦌𝑆 = 𝑇)
43	42	mpoeq3dva 7462	. . 3 ⊢ (𝜑 → (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ ⦋𝑅 / 𝑧⦌𝑆) = (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑇))
44	40, 43	eqtrid 2803	. 2 ⊢ (𝜑 → (𝑤 ∈ (𝐴 × 𝐵) ↦ ⦋⦋(2nd ‘𝑤) / 𝑦⦌⦋(1st ‘𝑤) / 𝑥⦌𝑅 / 𝑧⦌𝑆) = (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑇))
45	29, 44	eqtrd 2791	1 ⊢ (𝜑 → (𝐺 ∘ 𝐹) = (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝑇))

Syntax hints:   → wi 4   ∧ wa 398   = wceq 1554   ∈ wcel 2136  ∀wral 3070  ⦋csb 3847  ⟨cop 4582   ↦ cmpt 5175   × cxp 5638   ∘ ccom 5644  ⟶wf 6506  ‘cfv 6510   ∈ cmpo 7387  1^st c1st 7957  2^nd c2nd 7958

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1809  ax-4 1823  ax-5 1924  ax-6 1981  ax-7 2022  ax-8 2138  ax-9 2146  ax-10 2169  ax-11 2185  ax-12 2206  ax-ext 2728  ax-sep 5240  ax-nul 5250  ax-pr 5384  ax-un 7707

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 857  df-3an 1097  df-tru 1557  df-fal 1567  df-ex 1794  df-nf 1798  df-sb 2085  df-mo 2560  df-eu 2590  df-clab 2735  df-cleq 2748  df-clel 2831  df-nfc 2905  df-ne 2952  df-ral 3071  df-rex 3081  df-rab 3409  df-v 3450  df-sbc 3740  df-csb 3848  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-nul 4281  df-if 4475  df-sn 4577  df-pr 4579  df-op 4583  df-uni 4860  df-iun 4945  df-br 5095  df-opab 5157  df-mpt 5176  df-id 5535  df-xp 5646  df-rel 5647  df-cnv 5648  df-co 5649  df-dm 5650  df-rn 5651  df-res 5652  df-ima 5653  df-iota 6466  df-fun 6512  df-fn 6513  df-f 6514  df-fv 6518  df-oprab 7389  df-mpo 7390  df-1st 7959  df-2nd 7960

This theorem is referenced by:  evlselv  43119