Metamath Proof Explorer


Theorem o1bdd

Description: The defining property of an eventually bounded function. (Contributed by Mario Carneiro, 15-Sep-2014)

Ref Expression
Assertion o1bdd ⊢ F ∈ 𝑂⁡1 ∧ F : A ⟶ ℂ → ∃ x ∈ ℝ ∃ m ∈ ℝ ∀ y ∈ A x ≤ y → F ⁡ y ≤ m

Proof

Step Hyp Ref Expression
1 simpl ⊢ F ∈ 𝑂⁡1 ∧ F : A ⟶ ℂ → F ∈ 𝑂⁡1
2 simpr ⊢ F ∈ 𝑂⁡1 ∧ F : A ⟶ ℂ → F : A ⟶ ℂ
3 fdm ⊢ F : A ⟶ ℂ → dom ⁡ F = A
4 3 adantl ⊢ F ∈ 𝑂⁡1 ∧ F : A ⟶ ℂ → dom ⁡ F = A
5 o1dm ⊢ F ∈ 𝑂⁡1 → dom ⁡ F ⊆ ℝ
6 5 adantr ⊢ F ∈ 𝑂⁡1 ∧ F : A ⟶ ℂ → dom ⁡ F ⊆ ℝ
7 4 6 eqsstrrd ⊢ F ∈ 𝑂⁡1 ∧ F : A ⟶ ℂ → A ⊆ ℝ
8 elo12 ⊢ F : A ⟶ ℂ ∧ A ⊆ ℝ → F ∈ 𝑂⁡1 ↔ ∃ x ∈ ℝ ∃ m ∈ ℝ ∀ y ∈ A x ≤ y → F ⁡ y ≤ m
9 2 7 8 syl2anc ⊢ F ∈ 𝑂⁡1 ∧ F : A ⟶ ℂ → F ∈ 𝑂⁡1 ↔ ∃ x ∈ ℝ ∃ m ∈ ℝ ∀ y ∈ A x ≤ y → F ⁡ y ≤ m
10 1 9 mpbid ⊢ F ∈ 𝑂⁡1 ∧ F : A ⟶ ℂ → ∃ x ∈ ℝ ∃ m ∈ ℝ ∀ y ∈ A x ≤ y → F ⁡ y ≤ m