Theorem sbcie2s 17246

Description: A special version of class substitution commonly used for structures. (Contributed by Thierry Arnoux, 14-Mar-2019.) (Revised by SN, 2-Mar-2025.)

Hypotheses

Ref	Expression
sbcie2s.a	⊢ 𝐴 = (𝐸‘𝑊)
sbcie2s.b	⊢ 𝐵 = (𝐹‘𝑊)
sbcie2s.1	⊢ ((𝑎 = 𝐴 ∧ 𝑏 = 𝐵) → (𝜑 ↔ 𝜓))

Assertion

Ref	Expression
sbcie2s	⊢ (𝑤 = 𝑊 → ([(𝐸‘𝑤) / 𝑎][(𝐹‘𝑤) / 𝑏]𝜑 ↔ 𝜓))

Distinct variable groups:   𝑎,𝑏,𝑤   𝐸,𝑎,𝑏   𝐹,𝑏   𝑊,𝑎,𝑏   𝜓,𝑎,𝑏

Allowed substitution hints:   𝜑(𝑤, 𝑎, 𝑏)   𝜓(𝑤)   𝐴(𝑤, 𝑎, 𝑏)   𝐵(𝑤, 𝑎, 𝑏)   𝐸(𝑤)   𝐹(𝑤, 𝑎)   𝑊(𝑤)

Proof of Theorem sbcie2s

Step	Hyp	Ref	Expression
1		fvex 6901	. 2 ⊢ (𝐸‘𝑤) ∈ V
2		fvex 6901	. 2 ⊢ (𝐹‘𝑤) ∈ V
3		fveq2 6888	. . . . . 6 ⊢ (𝑤 = 𝑊 → (𝐸‘𝑤) = (𝐸‘𝑊))
4		sbcie2s.a	. . . . . 6 ⊢ 𝐴 = (𝐸‘𝑊)
5	3, 4	eqtr4di 2819	. . . . 5 ⊢ (𝑤 = 𝑊 → (𝐸‘𝑤) = 𝐴)
6	5	eqeq2d 2777	. . . 4 ⊢ (𝑤 = 𝑊 → (𝑎 = (𝐸‘𝑤) ↔ 𝑎 = 𝐴))
7	6	biimpd 232	. . 3 ⊢ (𝑤 = 𝑊 → (𝑎 = (𝐸‘𝑤) → 𝑎 = 𝐴))
8		fveq2 6888	. . . . . 6 ⊢ (𝑤 = 𝑊 → (𝐹‘𝑤) = (𝐹‘𝑊))
9		sbcie2s.b	. . . . . 6 ⊢ 𝐵 = (𝐹‘𝑊)
10	8, 9	eqtr4di 2819	. . . . 5 ⊢ (𝑤 = 𝑊 → (𝐹‘𝑤) = 𝐵)
11	10	eqeq2d 2777	. . . 4 ⊢ (𝑤 = 𝑊 → (𝑏 = (𝐹‘𝑤) ↔ 𝑏 = 𝐵))
12	11	biimpd 232	. . 3 ⊢ (𝑤 = 𝑊 → (𝑏 = (𝐹‘𝑤) → 𝑏 = 𝐵))
13		sbcie2s.1	. . . 4 ⊢ ((𝑎 = 𝐴 ∧ 𝑏 = 𝐵) → (𝜑 ↔ 𝜓))
14	13	a1i 11	. . 3 ⊢ (𝑤 = 𝑊 → ((𝑎 = 𝐴 ∧ 𝑏 = 𝐵) → (𝜑 ↔ 𝜓)))
15	7, 12, 14	syl2and 620	. 2 ⊢ (𝑤 = 𝑊 → ((𝑎 = (𝐸‘𝑤) ∧ 𝑏 = (𝐹‘𝑤)) → (𝜑 ↔ 𝜓)))
16	1, 2, 15	sbc2iedv 3823	1 ⊢ (𝑤 = 𝑊 → ([(𝐸‘𝑤) / 𝑎][(𝐹‘𝑤) / 𝑏]𝜑 ↔ 𝜓))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1570  [wsbc 3747  ‘cfv 6543

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2148  ax-9 2156  ax-ext 2738  ax-nul 5274

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-sb 2100  df-clab 2745  df-cleq 2758  df-clel 2841  df-ne 2962  df-rab 3420  df-v 3460  df-sbc 3748  df-dif 3911  df-un 3913  df-ss 3925  df-nul 4290  df-if 4493  df-sn 4595  df-pr 4597  df-op 4601  df-uni 4878  df-br 5115  df-iota 6499  df-fv 6551

This theorem is used by:  isassa  22043  istrkgc  28760  istrkgb  28761  istrkge  28763  istrkgl  28764  ishpg  29078  iscgra  29157