Metamath Proof Explorer


Theorem ordtuni

Description: Value of the order topology. (Contributed by Mario Carneiro, 3-Sep-2015)

Ref Expression
Hypotheses ordtval.1 𝑋 = dom 𝑅
ordtval.2 𝐴 = ran ( 𝑥𝑋 ↦ { 𝑦𝑋 ∣ ¬ 𝑦 𝑅 𝑥 } )
ordtval.3 𝐵 = ran ( 𝑥𝑋 ↦ { 𝑦𝑋 ∣ ¬ 𝑥 𝑅 𝑦 } )
Assertion ordtuni ( 𝑅𝑉𝑋 = ( { 𝑋 } ∪ ( 𝐴𝐵 ) ) )

Proof

Step Hyp Ref Expression
1 ordtval.1 𝑋 = dom 𝑅
2 ordtval.2 𝐴 = ran ( 𝑥𝑋 ↦ { 𝑦𝑋 ∣ ¬ 𝑦 𝑅 𝑥 } )
3 ordtval.3 𝐵 = ran ( 𝑥𝑋 ↦ { 𝑦𝑋 ∣ ¬ 𝑥 𝑅 𝑦 } )
4 dmexg ( 𝑅𝑉 → dom 𝑅 ∈ V )
5 1 4 eqeltrid ( 𝑅𝑉𝑋 ∈ V )
6 unisng ( 𝑋 ∈ V → { 𝑋 } = 𝑋 )
7 5 6 syl ( 𝑅𝑉 { 𝑋 } = 𝑋 )
8 7 uneq1d ( 𝑅𝑉 → ( { 𝑋 } ∪ ( 𝐴𝐵 ) ) = ( 𝑋 ( 𝐴𝐵 ) ) )
9 ssrab2 { 𝑦𝑋 ∣ ¬ 𝑦 𝑅 𝑥 } ⊆ 𝑋
10 5 adantr ( ( 𝑅𝑉𝑥𝑋 ) → 𝑋 ∈ V )
11 elpw2g ( 𝑋 ∈ V → ( { 𝑦𝑋 ∣ ¬ 𝑦 𝑅 𝑥 } ∈ 𝒫 𝑋 ↔ { 𝑦𝑋 ∣ ¬ 𝑦 𝑅 𝑥 } ⊆ 𝑋 ) )
12 10 11 syl ( ( 𝑅𝑉𝑥𝑋 ) → ( { 𝑦𝑋 ∣ ¬ 𝑦 𝑅 𝑥 } ∈ 𝒫 𝑋 ↔ { 𝑦𝑋 ∣ ¬ 𝑦 𝑅 𝑥 } ⊆ 𝑋 ) )
13 9 12 mpbiri ( ( 𝑅𝑉𝑥𝑋 ) → { 𝑦𝑋 ∣ ¬ 𝑦 𝑅 𝑥 } ∈ 𝒫 𝑋 )
14 13 fmpttd ( 𝑅𝑉 → ( 𝑥𝑋 ↦ { 𝑦𝑋 ∣ ¬ 𝑦 𝑅 𝑥 } ) : 𝑋 ⟶ 𝒫 𝑋 )
15 14 frnd ( 𝑅𝑉 → ran ( 𝑥𝑋 ↦ { 𝑦𝑋 ∣ ¬ 𝑦 𝑅 𝑥 } ) ⊆ 𝒫 𝑋 )
16 2 15 eqsstrid ( 𝑅𝑉𝐴 ⊆ 𝒫 𝑋 )
17 ssrab2 { 𝑦𝑋 ∣ ¬ 𝑥 𝑅 𝑦 } ⊆ 𝑋
18 elpw2g ( 𝑋 ∈ V → ( { 𝑦𝑋 ∣ ¬ 𝑥 𝑅 𝑦 } ∈ 𝒫 𝑋 ↔ { 𝑦𝑋 ∣ ¬ 𝑥 𝑅 𝑦 } ⊆ 𝑋 ) )
19 10 18 syl ( ( 𝑅𝑉𝑥𝑋 ) → ( { 𝑦𝑋 ∣ ¬ 𝑥 𝑅 𝑦 } ∈ 𝒫 𝑋 ↔ { 𝑦𝑋 ∣ ¬ 𝑥 𝑅 𝑦 } ⊆ 𝑋 ) )
20 17 19 mpbiri ( ( 𝑅𝑉𝑥𝑋 ) → { 𝑦𝑋 ∣ ¬ 𝑥 𝑅 𝑦 } ∈ 𝒫 𝑋 )
21 20 fmpttd ( 𝑅𝑉 → ( 𝑥𝑋 ↦ { 𝑦𝑋 ∣ ¬ 𝑥 𝑅 𝑦 } ) : 𝑋 ⟶ 𝒫 𝑋 )
22 21 frnd ( 𝑅𝑉 → ran ( 𝑥𝑋 ↦ { 𝑦𝑋 ∣ ¬ 𝑥 𝑅 𝑦 } ) ⊆ 𝒫 𝑋 )
23 3 22 eqsstrid ( 𝑅𝑉𝐵 ⊆ 𝒫 𝑋 )
24 16 23 unssd ( 𝑅𝑉 → ( 𝐴𝐵 ) ⊆ 𝒫 𝑋 )
25 sspwuni ( ( 𝐴𝐵 ) ⊆ 𝒫 𝑋 ( 𝐴𝐵 ) ⊆ 𝑋 )
26 24 25 sylib ( 𝑅𝑉 ( 𝐴𝐵 ) ⊆ 𝑋 )
27 ssequn2 ( ( 𝐴𝐵 ) ⊆ 𝑋 ↔ ( 𝑋 ( 𝐴𝐵 ) ) = 𝑋 )
28 26 27 sylib ( 𝑅𝑉 → ( 𝑋 ( 𝐴𝐵 ) ) = 𝑋 )
29 8 28 eqtr2d ( 𝑅𝑉𝑋 = ( { 𝑋 } ∪ ( 𝐴𝐵 ) ) )
30 uniun ( { 𝑋 } ∪ ( 𝐴𝐵 ) ) = ( { 𝑋 } ∪ ( 𝐴𝐵 ) )
31 29 30 eqtr4di ( 𝑅𝑉𝑋 = ( { 𝑋 } ∪ ( 𝐴𝐵 ) ) )