Theorem treq 5210

Description: Equality theorem for the transitive class predicate. (Contributed by NM, 17-Sep-1993.)

Assertion

Ref	Expression
treq	⊢ (𝐴 = 𝐵 → (Tr 𝐴 ↔ Tr 𝐵))

Proof of Theorem treq

Step	Hyp	Ref	Expression
1		unieq 4872	. . . 4 ⊢ (𝐴 = 𝐵 → ∪ 𝐴 = ∪ 𝐵)
2	1	sseq1d 3963	. . 3 ⊢ (𝐴 = 𝐵 → (∪ 𝐴 ⊆ 𝐴 ↔ ∪ 𝐵 ⊆ 𝐴))
3		sseq2 3958	. . 3 ⊢ (𝐴 = 𝐵 → (∪ 𝐵 ⊆ 𝐴 ↔ ∪ 𝐵 ⊆ 𝐵))
4	2, 3	bitrd 279	. 2 ⊢ (𝐴 = 𝐵 → (∪ 𝐴 ⊆ 𝐴 ↔ ∪ 𝐵 ⊆ 𝐵))
5		df-tr 5204	. 2 ⊢ (Tr 𝐴 ↔ ∪ 𝐴 ⊆ 𝐴)
6		df-tr 5204	. 2 ⊢ (Tr 𝐵 ↔ ∪ 𝐵 ⊆ 𝐵)
7	4, 5, 6	3bitr4g 314	1 ⊢ (𝐴 = 𝐵 → (Tr 𝐴 ↔ Tr 𝐵))

Syntax hints:   → wi 4   ↔ wb 206   = wceq 1541   ⊆ wss 3899  ∪ cuni 4861  Tr wtr 5203

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1968  ax-7 2009  ax-8 2115  ax-9 2123  ax-ext 2706

This theorem depends on definitions:  df-bi 207  df-an 396  df-tru 1544  df-ex 1781  df-sb 2068  df-clab 2713  df-cleq 2726  df-clel 2809  df-v 3440  df-ss 3916  df-uni 4862  df-tr 5204

This theorem is referenced by:  truni  5218  trint  5220  ordeq  6322  trcl  9635  tz9.1  9636  tz9.1c  9637  tctr  9645  tcmin  9646  tc2  9647  r1tr  9686  r1elssi  9715  tcrank  9794  iswun  10613  tskr1om2  10677  elgrug  10701  grutsk  10731  tz9.1regs  35239  dfon2lem1  35924  dfon2lem3  35926  dfon2lem4  35927  dfon2lem5  35928  dfon2lem6  35929  dfon2lem7  35930  dfon2lem8  35931  dfon2  35933  dford3lem1  43210  dford3lem2  43211  nadd1rabtr  43572  wfaxext  45176  wfaxrep  45177  wfaxpow  45180  wfaxinf2  45184  wfac8prim  45185