Theorem csbvarg 4382

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 3469	. 2 ⊢ (𝐴 ∈ 𝑉 → 𝐴 ∈ V)
2		df-csb 3848	. . . . . . 7 ⊢ ⦋𝑦 / 𝑥⦌𝑥 = {𝑧 ∣ [𝑦 / 𝑥]𝑧 ∈ 𝑥}
3		sbcel2gv 3805	. . . . . . . 8 ⊢ (𝑦 ∈ V → ([𝑦 / 𝑥]𝑧 ∈ 𝑥 ↔ 𝑧 ∈ 𝑦))
4	3	eqabcdv 2890	. . . . . . 7 ⊢ (𝑦 ∈ V → {𝑧 ∣ [𝑦 / 𝑥]𝑧 ∈ 𝑥} = 𝑦)
5	2, 4	eqtrid 2803	. . . . . 6 ⊢ (𝑦 ∈ V → ⦋𝑦 / 𝑥⦌𝑥 = 𝑦)
6	5	elv 3453	. . . . 5 ⊢ ⦋𝑦 / 𝑥⦌𝑥 = 𝑦
7	6	csbeq2i 3855	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌⦋𝑦 / 𝑥⦌𝑥 = ⦋𝐴 / 𝑦⦌𝑦
8		csbcow 3862	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌⦋𝑦 / 𝑥⦌𝑥 = ⦋𝐴 / 𝑥⦌𝑥
9		df-csb 3848	. . . 4 ⊢ ⦋𝐴 / 𝑦⦌𝑦 = {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦}
10	7, 8, 9	3eqtr3i 2787	. . 3 ⊢ ⦋𝐴 / 𝑥⦌𝑥 = {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦}
11		sbcel2gv 3805	. . . 4 ⊢ (𝐴 ∈ V → ([𝐴 / 𝑦]𝑧 ∈ 𝑦 ↔ 𝑧 ∈ 𝐴))
12	11	eqabcdv 2890	. . 3 ⊢ (𝐴 ∈ V → {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝑦} = 𝐴)
13	10, 12	eqtrid 2803	. 2 ⊢ (𝐴 ∈ V → ⦋𝐴 / 𝑥⦌𝑥 = 𝐴)
14	1, 13	syl 17	1 ⊢ (𝐴 ∈ 𝑉 → ⦋𝐴 / 𝑥⦌𝑥 = 𝐴)

Syntax hints:   → wi 4   = wceq 1554   ∈ wcel 2136  {cab 2734  Vcvv 3448  [wsbc 3739  ⦋csb 3847

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1809  ax-4 1823  ax-5 1924  ax-6 1981  ax-7 2022  ax-8 2138  ax-9 2146  ax-12 2206  ax-ext 2728

This theorem depends on definitions:  df-bi 209  df-an 399  df-tru 1557  df-ex 1794  df-sb 2085  df-clab 2735  df-cleq 2748  df-clel 2831  df-v 3450  df-sbc 3740  df-csb 3848

This theorem is referenced by:  csbvargi  4383  sbccsb2  4385  2nreu  4392  csbfv  6903  ixpsnval  8871  csbwrdg  14547  swrdspsleq  14669  prmgaplem7  17069  telgsums  20009  ixpsnbasval  21248  scmatscm  22546  pm2mpf1lem  22827  pm2mpcoe1  22833  idpm2idmp  22834  pm2mpmhmlem2  22852  monmat2matmon  22857  pm2mp  22858  fvmptnn04if  22882  chfacfscmulfsupp  22892  cayhamlem4  22921  divcncf  25482  opsbc2ie  32616  esum2dlem  34343  relowlpssretop  37806  rdgeqoa  37812  renegclALT  39535  cdlemk40  41489  tfsconcatfv  43866  iscard4  44057  minregex  44058  cotrclrcl  44266  frege124d  44285  frege70  44457  frege72  44459  frege77  44464  frege91  44478  frege92  44479  frege116  44503  frege118  44505  frege120  44507  rusbcALT  44962  onfrALTlem5  45066  onfrALTlem4  45067  onfrALTlem5VD  45408  iccelpart  47987  ply1mulgsumlem4  48959