Theorem csbvarg 4391

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 3478	. 2 ⊢ (𝐴 ∈ 𝑉 → 𝐴 ∈ V)
2		df-csb 3856	. . . . . . 7 ⊢ ⦋𝑦 / 𝑥⦌𝑥 = {𝑧 ∣ [𝑦 / 𝑥]𝑧 ∈ 𝑥}
3		sbcel2gv 3813	. . . . . . . 8 ⊢ (𝑦 ∈ V → ([𝑦 / 𝑥]𝑧 ∈ 𝑥 ↔ 𝑧 ∈ 𝑦))
4	3	eqabcdv 2899	. . . . . . 7 ⊢ (𝑦 ∈ V → {𝑧 ∣ [𝑦 / 𝑥]𝑧 ∈ 𝑥} = 𝑦)
5	2, 4	eqtrid 2812	. . . . . 6 ⊢ (𝑦 ∈ V → ⦋𝑦 / 𝑥⦌𝑥 = 𝑦)
6	5	elv 3462	. . . . 5 ⊢ ⦋𝑦 / 𝑥⦌𝑥 = 𝑦
7	6	csbeq2i 3863	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌⦋𝑦 / 𝑥⦌𝑥 = ⦋𝐴 / 𝑦⦌𝑦
8		csbcow 3870	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌⦋𝑦 / 𝑥⦌𝑥 = ⦋𝐴 / 𝑥⦌𝑥
9		df-csb 3856	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌𝑦 = {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦}
10	7, 8, 9	3eqtr3i 2796	. . 3 ⊢ ⦋𝐴 / 𝑥⦌𝑥 = {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦}
11		sbcel2gv 3813	. . . 4 ⊢ (𝐴 ∈ V → ([𝐴 / 𝑦]𝑧 ∈ 𝑦 ↔ 𝑧 ∈ 𝐴))
12	11	eqabcdv 2899	. . 3 ⊢ (𝐴 ∈ V → {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦} = 𝐴)
13	10, 12	eqtrid 2812	. 2 ⊢ (𝐴 ∈ V → ⦋𝐴 / 𝑥⦌𝑥 = 𝐴)
14	1, 13	syl 18	1 ⊢ (𝐴 ∈ 𝑉 → ⦋𝐴 / 𝑥⦌𝑥 = 𝐴)

Syntax hints:   → wi 4   = wceq 1563   ∈ wcel 2145  {cab 2743  Vcvv 3457  [wsbc 3747  ⦋csb 3855

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1818  ax-4 1832  ax-5 1933  ax-6 1990  ax-7 2031  ax-8 2147  ax-9 2155  ax-12 2215  ax-ext 2737

This theorem depends on definitions:  df-bi 210  df-an 401  df-tru 1566  df-ex 1803  df-sb 2094  df-clab 2744  df-cleq 2757  df-clel 2840  df-v 3459  df-sbc 3748  df-csb 3856

This theorem is referenced by:  csbvargi  4392  sbccsb2  4394  2nreu  4401  csbfv  6918  ixpsnval  8886  csbwrdg  14571  swrdspsleq  14693  prmgaplem7  17107  telgsums  20054  ixpsnbasval  21298  scmatscm  22631  pm2mpf1lem  22912  pm2mpcoe1  22918  idpm2idmp  22919  pm2mpmhmlem2  22937  monmat2matmon  22942  pm2mp  22943  fvmptnn04if  22967  chfacfscmulfsupp  22977  cayhamlem4  23006  divcncf  25567  opsbc2ie  32732  esum2dlem  34399  relowlpssretop  37870  rdgeqoa  37876  renegclALT  39599  cdlemk40  41553  tfsconcatfv  43930  iscard4  44121  minregex  44122  cotrclrcl  44330  frege124d  44349  frege70  44521  frege72  44523  frege77  44528  frege91  44542  frege92  44543  frege116  44567  frege118  44569  frege120  44571  rusbcALT  45012  onfrALTlem5  45116  onfrALTlem4  45117  onfrALTlem5VD  45458  iccelpart  48037  ply1mulgsumlem4  49020