Theorem csbvarg 3955

Description: The proper substitution of a class for setvar variable results in the class (if the class exists). (Contributed by NM, 10-Nov-2005.)

Assertion

Ref	Expression
csbvarg	⊢ (𝐴 ∈ 𝑉 → ⦋𝐴 / 𝑥⦌𝑥 = 𝐴)

Proof of Theorem csbvarg

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

Step	Hyp	Ref	Expression
1		elex 3185	. 2 ⊢ (𝐴 ∈ 𝑉 → 𝐴 ∈ V)
2		vex 3176	. . . . . 6 ⊢ 𝑦 ∈ V
3		df-csb 3500	. . . . . . 7 ⊢ ⦋𝑦 / 𝑥⦌𝑥 = {𝑧 ∣ [𝑦 / 𝑥]𝑧 ∈ 𝑥}
4		sbcel2gv 3463	. . . . . . . 8 ⊢ (𝑦 ∈ V → ([𝑦 / 𝑥]𝑧 ∈ 𝑥 ↔ 𝑧 ∈ 𝑦))
5	4	abbi1dv 2730	. . . . . . 7 ⊢ (𝑦 ∈ V → {𝑧 ∣ [𝑦 / 𝑥]𝑧 ∈ 𝑥} = 𝑦)
6	3, 5	syl5eq 2656	. . . . . 6 ⊢ (𝑦 ∈ V → ⦋𝑦 / 𝑥⦌𝑥 = 𝑦)
7	2, 6	ax-mp 5	. . . . 5 ⊢ ⦋𝑦 / 𝑥⦌𝑥 = 𝑦
8	7	csbeq2i 3945	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌⦋𝑦 / 𝑥⦌𝑥 = ⦋𝐴 / 𝑦⦌𝑦
9		csbco 3509	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌⦋𝑦 / 𝑥⦌𝑥 = ⦋𝐴 / 𝑥⦌𝑥
10		df-csb 3500	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌𝑦 = {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦}
11	8, 9, 10	3eqtr3i 2640	. . 3 ⊢ ⦋𝐴 / 𝑥⦌𝑥 = {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦}
12		sbcel2gv 3463	. . . 4 ⊢ (𝐴 ∈ V → ([𝐴 / 𝑦]𝑧 ∈ 𝑦 ↔ 𝑧 ∈ 𝐴))
13	12	abbi1dv 2730	. . 3 ⊢ (𝐴 ∈ V → {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦} = 𝐴)
14	11, 13	syl5eq 2656	. 2 ⊢ (𝐴 ∈ V → ⦋𝐴 / 𝑥⦌𝑥 = 𝐴)
15	1, 14	syl 17	1 ⊢ (𝐴 ∈ 𝑉 → ⦋𝐴 / 𝑥⦌𝑥 = 𝐴)

Syntax hints:   → wi 4   = wceq 1475   ∈ wcel 1977  {cab 2596  Vcvv 3173  [wsbc 3402  ⦋csb 3499

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590

This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-clab 2597  df-cleq 2603  df-clel 2606  df-v 3175  df-sbc 3403  df-csb 3500

This theorem is referenced by:  sbccsb2  3957  csbfv  6143  ixpsnval  7797  csbwrdg  13189  swrdspsleq  13301  prmgaplem7  15599  telgsums  18213  ixpsnbasval  19030  scmatscm  20138  pm2mpf1lem  20418  pm2mpcoe1  20424  idpm2idmp  20425  pm2mpmhmlem2  20443  monmat2matmon  20448  pm2mp  20449  fvmptnn04if  20473  chfacfscmulfsupp  20483  cayhamlem4  20512  nbgraopALT  25953  rusgrasn  26472  iuninc  28761  f1od2  28887  esum2dlem  29481  bnj110  30182  bj-sels  32143  relowlpssretop  32388  rdgeqoa  32394  finxpreclem4  32407  csbvargi  33091  renegclALT  33267  cdlemk40  35223  brtrclfv2  37038  cotrclrcl  37053  frege124d  37072  frege70  37247  frege72  37249  frege77  37254  frege91  37268  frege92  37269  frege116  37293  frege118  37295  frege120  37297  rusbcALT  37662  onfrALTlem5  37778  onfrALTlem4  37779  onfrALTlem5VD  38143  onfrALTlem4VD  38144  divcncf  38769  iccelpart  39971  ply1mulgsumlem4  41971