Metamath Proof Explorer


Theorem iniin2

Description: Indexed intersection of intersection. (Contributed by Glauco Siliprandi, 23-Oct-2021)

Ref Expression
Assertion iniin2 ( 𝐴 ≠ ∅ → ( 𝐵 ∩ ∩ 𝑥 ∈ 𝐴 𝐶 ) = ∩ 𝑥 ∈ 𝐴 ( 𝐵 ∩ 𝐶 ) )

Proof

Step Hyp Ref Expression
1 iinin2 ⊢ ( 𝐴 ≠ ∅ → ∩ 𝑥 ∈ 𝐴 ( 𝐵 ∩ 𝐶 ) = ( 𝐵 ∩ ∩ 𝑥 ∈ 𝐴 𝐶 ) )
2 1 eqcomd ⊢ ( 𝐴 ≠ ∅ → ( 𝐵 ∩ ∩ 𝑥 ∈ 𝐴 𝐶 ) = ∩ 𝑥 ∈ 𝐴 ( 𝐵 ∩ 𝐶 ) )