Metamath Proof Explorer


Theorem iblmbf

Description: An integrable function is measurable. (Contributed by Mario Carneiro, 7-Jul-2014)

Ref Expression
Assertion iblmbf ⊢ F ∈ 𝐿 1 → F ∈ MblFn

Proof

Step Hyp Ref Expression
1 df-ibl ⊢ 𝐿 1 = f ∈ MblFn | ∀ k ∈ 0 … 3 ∫ 2 ⁡ x ∈ ℝ ⟼ ⦋ ℜ ⁡ f ⁡ x i k / y⦌ if x ∈ dom ⁡ f ∧ 0 ≤ y y 0 ∈ ℝ
2 1 ssrab3 ⊢ 𝐿 1 ⊆ MblFn
3 2 sseli ⊢ F ∈ 𝐿 1 → F ∈ MblFn