Metamath Proof Explorer


Theorem pnfged

Description: Plus infinity is an upper bound for extended reals. (Contributed by Glauco Siliprandi, 5-Feb-2022)

Ref Expression
Hypothesis pnfged.1 ⊢ φ → A ∈ ℝ *
Assertion pnfged ⊢ φ → A ≤ +∞

Proof

Step Hyp Ref Expression
1 pnfged.1 ⊢ φ → A ∈ ℝ *
2 pnfge ⊢ A ∈ ℝ * → A ≤ +∞
3 1 2 syl ⊢ φ → A ≤ +∞