Theorem csbie 3885

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 3851	. 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 3783	. . 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 3441  [wsbc 3741  ⦋csb 3850

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 3742  df-csb 3851

This theorem is referenced by:  pofun  5551  eqerlem  8673  mptnn0fsuppd  13925  fsum  15647  fsumcnv  15700  fsumshftm  15708  fsum0diag2  15710  fprod  15868  fprodcnv  15910  bpolyval  15976  ruclem1  16160  odfval  19465  odval  19467  psrass1lem  21892  selvval  22082  mamufval  22340  pm2mpval  22743  isibl  25726  dfitg  25730  dvfsumlem2  25993  dvfsumlem2OLD  25994  fsumdvdsmul  27165  fsumdvdsmulOLD  27167  precsexlem3  28190  disjxpin  32645  gsummulsubdishift2s  33135  poimirlem1  37793  poimirlem5  37797  poimirlem15  37807  poimirlem16  37808  poimirlem17  37809  poimirlem19  37811  poimirlem20  37812  poimirlem22  37814  poimirlem24  37816  poimirlem28  37820  evlselv  42866  fphpd  43094  monotuz  43219  oddcomabszz  43222  fnwe2val  43327  fnwe2lem1  43328  dfswapf2  49542  dfinito4  49782