Metamath Proof Explorer


Theorem hoissrrn2

Description: A half-open interval is a subset of R^n . (Contributed by Glauco Siliprandi, 21-Nov-2020)

Ref Expression
Hypotheses hoissrrn2.kph ⊢ Ⅎ k φ
hoissrrn2.a ⊢ φ ∧ k ∈ X → A ∈ ℝ
hoissrrn2.b ⊢ φ ∧ k ∈ X → B ∈ ℝ *
Assertion hoissrrn2 ⊢ φ → ⨉ k ∈ X A B ⊆ ℝ X

Proof

Step Hyp Ref Expression
1 hoissrrn2.kph ⊢ Ⅎ k φ
2 hoissrrn2.a ⊢ φ ∧ k ∈ X → A ∈ ℝ
3 hoissrrn2.b ⊢ φ ∧ k ∈ X → B ∈ ℝ *
4 ovex ⊢ A B ∈ V
5 4 rgenw ⊢ ∀ k ∈ X A B ∈ V
6 ixpssmapg ⊢ ∀ k ∈ X A B ∈ V → ⨉ k ∈ X A B ⊆ ⋃ k ∈ X A B X
7 5 6 ax-mp ⊢ ⨉ k ∈ X A B ⊆ ⋃ k ∈ X A B X
8 7 a1i ⊢ φ → ⨉ k ∈ X A B ⊆ ⋃ k ∈ X A B X
9 reex ⊢ ℝ ∈ V
10 9 a1i ⊢ φ → ℝ ∈ V
11 icossre ⊢ A ∈ ℝ ∧ B ∈ ℝ * → A B ⊆ ℝ
12 2 3 11 syl2anc ⊢ φ ∧ k ∈ X → A B ⊆ ℝ
13 12 ex ⊢ φ → k ∈ X → A B ⊆ ℝ
14 1 13 ralrimi ⊢ φ → ∀ k ∈ X A B ⊆ ℝ
15 iunss ⊢ ⋃ k ∈ X A B ⊆ ℝ ↔ ∀ k ∈ X A B ⊆ ℝ
16 14 15 sylibr ⊢ φ → ⋃ k ∈ X A B ⊆ ℝ
17 mapss ⊢ ℝ ∈ V ∧ ⋃ k ∈ X A B ⊆ ℝ → ⋃ k ∈ X A B X ⊆ ℝ X
18 10 16 17 syl2anc ⊢ φ → ⋃ k ∈ X A B X ⊆ ℝ X
19 8 18 sstrd ⊢ φ → ⨉ k ∈ X A B ⊆ ℝ X