Theorem sbcheg 41387

Description: Distribute proper substitution through herditary relation. (Contributed by RP, 29-Jun-2020.)

Assertion

Ref	Expression
sbcheg	⊢ (𝐴 ∈ 𝑉 → ([𝐴 / 𝑥]𝐵 hereditary 𝐶 ↔ ⦋𝐴 / 𝑥⦌𝐵 hereditary ⦋𝐴 / 𝑥⦌𝐶))

Proof of Theorem sbcheg

Step	Hyp	Ref	Expression
1		sbcssg 4454	. . 3 ⊢ (𝐴 ∈ 𝑉 → ([𝐴 / 𝑥](𝐵 “ 𝐶) ⊆ 𝐶 ↔ ⦋𝐴 / 𝑥⦌(𝐵 “ 𝐶) ⊆ ⦋𝐴 / 𝑥⦌𝐶))
2		csbima12 5987	. . . . 5 ⊢ ⦋𝐴 / 𝑥⦌(𝐵 “ 𝐶) = (⦋𝐴 / 𝑥⦌𝐵 “ ⦋𝐴 / 𝑥⦌𝐶)
3	2	a1i 11	. . . 4 ⊢ (𝐴 ∈ 𝑉 → ⦋𝐴 / 𝑥⦌(𝐵 “ 𝐶) = (⦋𝐴 / 𝑥⦌𝐵 “ ⦋𝐴 / 𝑥⦌𝐶))
4	3	sseq1d 3952	. . 3 ⊢ (𝐴 ∈ 𝑉 → (⦋𝐴 / 𝑥⦌(𝐵 “ 𝐶) ⊆ ⦋𝐴 / 𝑥⦌𝐶 ↔ (⦋𝐴 / 𝑥⦌𝐵 “ ⦋𝐴 / 𝑥⦌𝐶) ⊆ ⦋𝐴 / 𝑥⦌𝐶))
5	1, 4	bitrd 278	. 2 ⊢ (𝐴 ∈ 𝑉 → ([𝐴 / 𝑥](𝐵 “ 𝐶) ⊆ 𝐶 ↔ (⦋𝐴 / 𝑥⦌𝐵 “ ⦋𝐴 / 𝑥⦌𝐶) ⊆ ⦋𝐴 / 𝑥⦌𝐶))
6		df-he 41381	. . 3 ⊢ (𝐵 hereditary 𝐶 ↔ (𝐵 “ 𝐶) ⊆ 𝐶)
7	6	sbcbii 3776	. 2 ⊢ ([𝐴 / 𝑥]𝐵 hereditary 𝐶 ↔ [𝐴 / 𝑥](𝐵 “ 𝐶) ⊆ 𝐶)
8		df-he 41381	. 2 ⊢ (⦋𝐴 / 𝑥⦌𝐵 hereditary ⦋𝐴 / 𝑥⦌𝐶 ↔ (⦋𝐴 / 𝑥⦌𝐵 “ ⦋𝐴 / 𝑥⦌𝐶) ⊆ ⦋𝐴 / 𝑥⦌𝐶)
9	5, 7, 8	3bitr4g 314	1 ⊢ (𝐴 ∈ 𝑉 → ([𝐴 / 𝑥]𝐵 hereditary 𝐶 ↔ ⦋𝐴 / 𝑥⦌𝐵 hereditary ⦋𝐴 / 𝑥⦌𝐶))

Syntax hints:   → wi 4   ↔ wb 205   = wceq 1539   ∈ wcel 2106  [wsbc 3716  ⦋csb 3832   ⊆ wss 3887   “ cima 5592   hereditary whe 41380

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2709  ax-sep 5223  ax-nul 5230  ax-pr 5352

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 845  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1783  df-nf 1787  df-sb 2068  df-clab 2716  df-cleq 2730  df-clel 2816  df-nfc 2889  df-rab 3073  df-v 3434  df-sbc 3717  df-csb 3833  df-dif 3890  df-un 3892  df-in 3894  df-ss 3904  df-nul 4257  df-if 4460  df-sn 4562  df-pr 4564  df-op 4568  df-br 5075  df-opab 5137  df-xp 5595  df-cnv 5597  df-dm 5599  df-rn 5600  df-res 5601  df-ima 5602  df-he 41381

This theorem is referenced by:  frege77  41548