Theorem chm1i 31403

Description: Meet with lattice one in C_ℋ. (Contributed by NM, 24-Oct-1999.) (New usage is discouraged.)

Hypothesis

Ref	Expression
ch0le.1	⊢ 𝐴 ∈ Cℋ

Assertion

Ref	Expression
chm1i	⊢ (𝐴 ∩ ℋ) = 𝐴

Proof of Theorem chm1i

Step	Hyp	Ref	Expression
1		ch0le.1	. . 3 ⊢ 𝐴 ∈ Cℋ
2	1	chssii 31178	. 2 ⊢ 𝐴 ⊆ ℋ
3		dfss2 3949	. 2 ⊢ (𝐴 ⊆ ℋ ↔ (𝐴 ∩ ℋ) = 𝐴)
4	2, 3	mpbi 230	1 ⊢ (𝐴 ∩ ℋ) = 𝐴

Syntax hints:   = wceq 1539   ∈ wcel 2107   ∩ cin 3930   ⊆ wss 3931   ℋchba 30866   C_ℋ cch 30876

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1794  ax-4 1808  ax-5 1909  ax-6 1966  ax-7 2006  ax-8 2109  ax-9 2117  ax-ext 2706  ax-sep 5276  ax-hilex 30946

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1779  df-sb 2064  df-clab 2713  df-cleq 2726  df-clel 2808  df-rab 3420  df-v 3465  df-dif 3934  df-un 3936  df-in 3938  df-ss 3948  df-nul 4314  df-if 4506  df-pw 4582  df-sn 4607  df-pr 4609  df-op 4613  df-uni 4888  df-br 5124  df-opab 5186  df-xp 5671  df-cnv 5673  df-dm 5675  df-rn 5676  df-res 5677  df-ima 5678  df-iota 6494  df-fv 6549  df-ov 7416  df-sh 31154  df-ch 31168

This theorem is referenced by:  stcltrlem1  32223