Metamath Proof Explorer


Theorem xrsex

Description: The extended real structure is a set. (Contributed by Mario Carneiro, 21-Aug-2015)

Ref Expression
Assertion xrsex ⊢ ℝ 𝑠 * ∈ V

Proof

Step Hyp Ref Expression
1 df-xrs ⊢ ℝ 𝑠 * = Base ndx ℝ * + ndx + 𝑒 ⋅ ndx ⋅ 𝑒 ∪ TopSet ⁡ ndx ordTop ⁡ ≤ ≤ ndx ≤ dist ⁡ ndx x ∈ ℝ * , y ∈ ℝ * ⟼ if x ≤ y y + 𝑒 − x x + 𝑒 − y
2 tpex ⊢ Base ndx ℝ * + ndx + 𝑒 ⋅ ndx ⋅ 𝑒 ∈ V
3 tpex ⊢ TopSet ⁡ ndx ordTop ⁡ ≤ ≤ ndx ≤ dist ⁡ ndx x ∈ ℝ * , y ∈ ℝ * ⟼ if x ≤ y y + 𝑒 − x x + 𝑒 − y ∈ V
4 2 3 unex ⊢ Base ndx ℝ * + ndx + 𝑒 ⋅ ndx ⋅ 𝑒 ∪ TopSet ⁡ ndx ordTop ⁡ ≤ ≤ ndx ≤ dist ⁡ ndx x ∈ ℝ * , y ∈ ℝ * ⟼ if x ≤ y y + 𝑒 − x x + 𝑒 − y ∈ V
5 1 4 eqeltri ⊢ ℝ 𝑠 * ∈ V