Theorem nfcsb1d 3887

Description: Bound-variable hypothesis builder for substitution into a class. (Contributed by Mario Carneiro, 12-Oct-2016.)

Hypothesis

Ref	Expression
nfcsb1d.1	⊢ (𝜑 → Ⅎ𝑥𝐴)

Assertion

Ref	Expression
nfcsb1d	⊢ (𝜑 → Ⅎ𝑥⦋𝐴 / 𝑥⦌𝐵)

Proof of Theorem nfcsb1d

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-csb 3866	. 2 ⊢ ⦋𝐴 / 𝑥⦌𝐵 = {𝑦 ∣ [𝐴 / 𝑥]𝑦 ∈ 𝐵}
2		nfv 1914	. . 3 ⊢ Ⅎ𝑦𝜑
3		nfcsb1d.1	. . . 4 ⊢ (𝜑 → Ⅎ𝑥𝐴)
4	3	nfsbc1d 3774	. . 3 ⊢ (𝜑 → Ⅎ𝑥[𝐴 / 𝑥]𝑦 ∈ 𝐵)
5	2, 4	nfabdw 2914	. 2 ⊢ (𝜑 → Ⅎ𝑥{𝑦 ∣ [𝐴 / 𝑥]𝑦 ∈ 𝐵})
6	1, 5	nfcxfrd 2891	1 ⊢ (𝜑 → Ⅎ𝑥⦋𝐴 / 𝑥⦌𝐵)

Syntax hints:   → wi 4   ∈ wcel 2109  {cab 2708  Ⅎwnfc 2877  [wsbc 3756  ⦋csb 3865

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-10 2142  ax-11 2158  ax-12 2178  ax-ext 2702

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-ex 1780  df-nf 1784  df-sb 2066  df-clab 2709  df-cleq 2722  df-clel 2804  df-nfc 2879  df-sbc 3757  df-csb 3866

This theorem is referenced by:  nfcsb1  3888  riotaeqimp  7373