Metamath Proof Explorer


Theorem xlimcl

Description: The limit of a sequence of extended real numbers is an extended real number. (Contributed by Glauco Siliprandi, 5-Feb-2022)

Ref Expression
Assertion xlimcl ( 𝐹 ~~>* 𝐴 → 𝐴 ∈ ℝ* )

Proof

Step Hyp Ref Expression
1 letopon ⊢ ( ordTop ‘ ≤ ) ∈ ( TopOn ‘ ℝ* )
2 df-xlim ⊢ ~~>* = ( ⇝𝑡 ‘ ( ordTop ‘ ≤ ) )
3 2 breqi ⊢ ( 𝐹 ~~>* 𝐴 ↔ 𝐹 ( ⇝𝑡 ‘ ( ordTop ‘ ≤ ) ) 𝐴 )
4 3 biimpi ⊢ ( 𝐹 ~~>* 𝐴 → 𝐹 ( ⇝𝑡 ‘ ( ordTop ‘ ≤ ) ) 𝐴 )
5 lmcl ⊢ ( ( ( ordTop ‘ ≤ ) ∈ ( TopOn ‘ ℝ* ) ∧ 𝐹 ( ⇝𝑡 ‘ ( ordTop ‘ ≤ ) ) 𝐴 ) → 𝐴 ∈ ℝ* )
6 1 4 5 sylancr ⊢ ( 𝐹 ~~>* 𝐴 → 𝐴 ∈ ℝ* )