Theorem csbie 3887

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 3853	. 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 2848	. . . 4 ⊢ (𝑥 = 𝐴 → (𝑦 ∈ 𝐵 ↔ 𝑦 ∈ 𝐶))
5	2, 4	sbcie 3784	. . 3 ⊢ ([𝐴 / 𝑥]𝑦 ∈ 𝐵 ↔ 𝑦 ∈ 𝐶)
6	5	abbii 2829	. 2 ⊢ {𝑦 ∣ [𝐴 / 𝑥]𝑦 ∈ 𝐵} = {𝑦 ∣ 𝑦 ∈ 𝐶}
7		abid2 2899	. 2 ⊢ {𝑦 ∣ 𝑦 ∈ 𝐶} = 𝐶
8	1, 6, 7	3eqtri 2789	1 ⊢ ⦋𝐴 / 𝑥⦌𝐵 = 𝐶

This proof depends on syntax axioms:   → wi 4   = wceq 1569   ∈ wcel 2142  {cab 2740  Vcvv 3454  [wsbc 3743  ⦋csb 3852

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838  ax-5 1939  ax-6 1996  ax-7 2037  ax-8 2144  ax-9 2152  ax-ext 2734

This proof depends on definitions:  df-bi 210  df-an 401  df-tru 1572  df-ex 1809  df-sb 2096  df-clab 2741  df-cleq 2754  df-clel 2837  df-sbc 3744  df-csb 3853

This theorem is used by:  pofun  5586  eqerlem  8728  mptnn0fsuppd  14041  fsum  15778  fsumcnv  15831  fsumshftm  15839  fsum0diag2  15841  fprod  16002  fprodcnv  16044  bpolyval  16109  ruclem1  16293  odfval  19608  odval  19610  psrass1lem  22094  selvval  22282  mamufval  22560  pm2mpval  22963  isibl  25935  dfitg  25939  dvfsumlem2  26197  fsumdvdsmul  27370  precsexlem3  28413  disjxpin  32944  gsummulsubdishift2s  33400  nmulprop  36690  poimirlem1  38300  poimirlem5  38304  poimirlem15  38314  poimirlem16  38315  poimirlem17  38316  poimirlem19  38318  poimirlem20  38319  poimirlem22  38321  poimirlem24  38323  poimirlem28  38327  evlselv  43349  fphpd  43571  monotuz  43696  oddcomabszz  43699  fnwe2val  43804  fnwe2lem1  43805  dfswapf2  50067  dfinito4  50307