Theorem csbvarg 4398

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 3474	. 2 ⊢ (𝐴 ∈ 𝑉 → 𝐴 ∈ V)
2		df-csb 3853	. . . . . . 7 ⊢ ⦋𝑦 / 𝑥⦌𝑥 = {𝑧 ∣ [𝑦 / 𝑥]𝑧 ∈ 𝑥}
3		sbcel2gv 3809	. . . . . . . 8 ⊢ (𝑦 ∈ V → ([𝑦 / 𝑥]𝑧 ∈ 𝑥 ↔ 𝑧 ∈ 𝑦))
4	3	eqabcdv 2895	. . . . . . 7 ⊢ (𝑦 ∈ V → {𝑧 ∣ [𝑦 / 𝑥]𝑧 ∈ 𝑥} = 𝑦)
5	2, 4	eqtrid 2808	. . . . . 6 ⊢ (𝑦 ∈ V → ⦋𝑦 / 𝑥⦌𝑥 = 𝑦)
6	5	elv 3458	. . . . 5 ⊢ ⦋𝑦 / 𝑥⦌𝑥 = 𝑦
7	6	csbeq2i 3860	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌⦋𝑦 / 𝑥⦌𝑥 = ⦋𝐴 / 𝑦⦌𝑦
8		csbcow 3867	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌⦋𝑦 / 𝑥⦌𝑥 = ⦋𝐴 / 𝑥⦌𝑥
9		df-csb 3853	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌𝑦 = {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦}
10	7, 8, 9	3eqtr3i 2792	. . 3 ⊢ ⦋𝐴 / 𝑥⦌𝑥 = {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦}
11		sbcel2gv 3809	. . . 4 ⊢ (𝐴 ∈ V → ([𝐴 / 𝑦]𝑧 ∈ 𝑦 ↔ 𝑧 ∈ 𝐴))
12	11	eqabcdv 2895	. . 3 ⊢ (𝐴 ∈ V → {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦} = 𝐴)
13	10, 12	eqtrid 2808	. 2 ⊢ (𝐴 ∈ V → ⦋𝐴 / 𝑥⦌𝑥 = 𝐴)
14	1, 13	syl 18	1 ⊢ (𝐴 ∈ 𝑉 → ⦋𝐴 / 𝑥⦌𝑥 = 𝐴)

Syntax hints:   → wi 4   = wceq 1568   ∈ wcel 2141  {cab 2739  Vcvv 3453  [wsbc 3743  ⦋csb 3852

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1823  ax-4 1837  ax-5 1938  ax-6 1995  ax-7 2036  ax-8 2143  ax-9 2151  ax-12 2211  ax-ext 2733

This theorem depends on definitions:  df-bi 210  df-an 401  df-tru 1571  df-ex 1808  df-sb 2095  df-clab 2740  df-cleq 2753  df-clel 2836  df-v 3455  df-sbc 3744  df-csb 3853

This theorem is referenced by:  csbvargi  4399  sbccsb2  4401  2nreu  4408  csbfv  6928  ixpsnval  8897  csbwrdg  14581  swrdspsleq  14703  prmgaplem7  17116  telgsums  20062  ixpsnbasval  21308  scmatscm  22649  pm2mpf1lem  22930  pm2mpcoe1  22936  idpm2idmp  22937  pm2mpmhmlem2  22955  monmat2matmon  22960  pm2mp  22961  fvmptnn04if  22985  chfacfscmulfsupp  22995  cayhamlem4  23024  divcncf  25585  opsbc2ie  32788  esum2dlem  34448  relowlpssretop  37976  rdgeqoa  37982  renegclALT  39705  cdlemk40  41659  tfsconcatfv  44038  iscard4  44229  minregex  44230  cotrclrcl  44438  frege124d  44457  frege70  44629  frege72  44631  frege77  44636  frege91  44650  frege92  44651  frege116  44675  frege118  44677  frege120  44679  rusbcALT  45118  onfrALTlem5  45221  onfrALTlem4  45222  onfrALTlem5VD  45563  iccelpart  48149  ply1mulgsumlem4  49136