Theorem csbie 3873

Description: Conversion of implicit substitution to explicit substitution into a class. (Contributed by AV, 2-Dec-2019.) Reduce axiom usage. (Revised by GG, 15-Oct-2024.)

Hypotheses

Ref	Expression
csbie.1	⊢ 𝐴 ∈ V
csbie.2	⊢ (𝑥 = 𝐴 → 𝐵 = 𝐶)

Assertion

Ref	Expression
csbie	⊢ ⦋𝐴 / 𝑥⦌𝐵 = 𝐶

Distinct variable groups:   𝑥,𝐴   𝑥,𝐶

Allowed substitution hint:   𝐵(𝑥)

Proof of Theorem csbie

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-csb 3839	. 2 ⊢ ⦋𝐴 / 𝑥⦌𝐵 = {𝑦 ∣ [𝐴 / 𝑥]𝑦 ∈ 𝐵}
2		csbie.1	. . . 4 ⊢ 𝐴 ∈ V
3		csbie.2	. . . . 5 ⊢ (𝑥 = 𝐴 → 𝐵 = 𝐶)
4	3	eleq2d 2823	. . . 4 ⊢ (𝑥 = 𝐴 → (𝑦 ∈ 𝐵 ↔ 𝑦 ∈ 𝐶))
5	2, 4	sbcie 3771	. . 3 ⊢ ([𝐴 / 𝑥]𝑦 ∈ 𝐵 ↔ 𝑦 ∈ 𝐶)
6	5	abbii 2804	. 2 ⊢ {𝑦 ∣ [𝐴 / 𝑥]𝑦 ∈ 𝐵} = {𝑦 ∣ 𝑦 ∈ 𝐶}
7		abid2 2874	. 2 ⊢ {𝑦 ∣ 𝑦 ∈ 𝐶} = 𝐶
8	1, 6, 7	3eqtri 2764	1 ⊢ ⦋𝐴 / 𝑥⦌𝐵 = 𝐶

Syntax hints:   → wi 4   = wceq 1542   ∈ wcel 2114  {cab 2715  Vcvv 3430  [wsbc 3729  ⦋csb 3838

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-ext 2709

This theorem depends on definitions:  df-bi 207  df-an 396  df-tru 1545  df-ex 1782  df-sb 2069  df-clab 2716  df-cleq 2729  df-clel 2812  df-sbc 3730  df-csb 3839

This theorem is referenced by:  pofun  5548  eqerlem  8670  mptnn0fsuppd  13949  fsum  15671  fsumcnv  15724  fsumshftm  15732  fsum0diag2  15734  fprod  15895  fprodcnv  15937  bpolyval  16003  ruclem1  16187  odfval  19496  odval  19498  psrass1lem  21920  selvval  22110  mamufval  22366  pm2mpval  22769  isibl  25741  dfitg  25745  dvfsumlem2  26005  dvfsumlem2OLD  26006  fsumdvdsmul  27176  fsumdvdsmulOLD  27178  precsexlem3  28220  disjxpin  32678  gsummulsubdishift2s  33152  poimirlem1  37953  poimirlem5  37957  poimirlem15  37967  poimirlem16  37968  poimirlem17  37969  poimirlem19  37971  poimirlem20  37972  poimirlem22  37974  poimirlem24  37976  poimirlem28  37980  evlselv  43031  fphpd  43259  monotuz  43384  oddcomabszz  43387  fnwe2val  43492  fnwe2lem1  43493  dfswapf2  49733  dfinito4  49973