Theorem csbafv12g 43693

Description: Move class substitution in and out of a function value, analogous to csbfv12 6688, with a direct proof proposed by Mario Carneiro, analogous to csbov123 7177. (Contributed by Alexander van der Vekens, 23-Jul-2017.)

Assertion

Ref	Expression
csbafv12g	⊢ (𝐴 ∈ 𝑉 → ⦋𝐴 / 𝑥⦌(𝐹'''𝐵) = (⦋𝐴 / 𝑥⦌𝐹'''⦋𝐴 / 𝑥⦌𝐵))

Proof of Theorem csbafv12g

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		csbeq1 3831	. . 3 ⊢ (𝑦 = 𝐴 → ⦋𝑦 / 𝑥⦌(𝐹'''𝐵) = ⦋𝐴 / 𝑥⦌(𝐹'''𝐵))
2		csbeq1 3831	. . . 4 ⊢ (𝑦 = 𝐴 → ⦋𝑦 / 𝑥⦌𝐹 = ⦋𝐴 / 𝑥⦌𝐹)
3		csbeq1 3831	. . . 4 ⊢ (𝑦 = 𝐴 → ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝐴 / 𝑥⦌𝐵)
4	2, 3	afveq12d 43689	. . 3 ⊢ (𝑦 = 𝐴 → (⦋𝑦 / 𝑥⦌𝐹'''⦋𝑦 / 𝑥⦌𝐵) = (⦋𝐴 / 𝑥⦌𝐹'''⦋𝐴 / 𝑥⦌𝐵))
5	1, 4	eqeq12d 2814	. 2 ⊢ (𝑦 = 𝐴 → (⦋𝑦 / 𝑥⦌(𝐹'''𝐵) = (⦋𝑦 / 𝑥⦌𝐹'''⦋𝑦 / 𝑥⦌𝐵) ↔ ⦋𝐴 / 𝑥⦌(𝐹'''𝐵) = (⦋𝐴 / 𝑥⦌𝐹'''⦋𝐴 / 𝑥⦌𝐵)))
6		vex 3444	. . 3 ⊢ 𝑦 ∈ V
7		nfcsb1v 3852	. . . 4 ⊢ Ⅎ𝑥⦋𝑦 / 𝑥⦌𝐹
8		nfcsb1v 3852	. . . 4 ⊢ Ⅎ𝑥⦋𝑦 / 𝑥⦌𝐵
9	7, 8	nfafv 43692	. . 3 ⊢ Ⅎ𝑥(⦋𝑦 / 𝑥⦌𝐹'''⦋𝑦 / 𝑥⦌𝐵)
10		csbeq1a 3842	. . . 4 ⊢ (𝑥 = 𝑦 → 𝐹 = ⦋𝑦 / 𝑥⦌𝐹)
11		csbeq1a 3842	. . . 4 ⊢ (𝑥 = 𝑦 → 𝐵 = ⦋𝑦 / 𝑥⦌𝐵)
12	10, 11	afveq12d 43689	. . 3 ⊢ (𝑥 = 𝑦 → (𝐹'''𝐵) = (⦋𝑦 / 𝑥⦌𝐹'''⦋𝑦 / 𝑥⦌𝐵))
13	6, 9, 12	csbief 3862	. 2 ⊢ ⦋𝑦 / 𝑥⦌(𝐹'''𝐵) = (⦋𝑦 / 𝑥⦌𝐹'''⦋𝑦 / 𝑥⦌𝐵)
14	5, 13	vtoclg 3515	1 ⊢ (𝐴 ∈ 𝑉 → ⦋𝐴 / 𝑥⦌(𝐹'''𝐵) = (⦋𝐴 / 𝑥⦌𝐹'''⦋𝐴 / 𝑥⦌𝐵))

Syntax hints:   → wi 4   = wceq 1538   ∈ wcel 2111  ⦋csb 3828  '''cafv 43673

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1911  ax-6 1970  ax-7 2015  ax-8 2113  ax-9 2121  ax-10 2142  ax-11 2158  ax-12 2175  ax-ext 2770  ax-sep 5167  ax-nul 5174  ax-pow 5231  ax-pr 5295

This theorem depends on definitions:  df-bi 210  df-an 400  df-or 845  df-3an 1086  df-tru 1541  df-fal 1551  df-ex 1782  df-nf 1786  df-sb 2070  df-mo 2598  df-eu 2629  df-clab 2777  df-cleq 2791  df-clel 2870  df-nfc 2938  df-ne 2988  df-ral 3111  df-rex 3112  df-rab 3115  df-v 3443  df-sbc 3721  df-csb 3829  df-dif 3884  df-un 3886  df-in 3888  df-ss 3898  df-nul 4244  df-if 4426  df-sn 4526  df-pr 4528  df-op 4532  df-uni 4801  df-int 4839  df-br 5031  df-opab 5093  df-id 5425  df-xp 5525  df-rel 5526  df-cnv 5527  df-co 5528  df-dm 5529  df-res 5531  df-iota 6283  df-fun 6326  df-fv 6332  df-aiota 43642  df-dfat 43675  df-afv 43676

This theorem is referenced by: (None)