Metamath Proof Explorer


Theorem iniin1

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

Ref Expression
Assertion iniin1 ( 𝐴 ≠ ∅ → ( 𝑥𝐴 𝐶𝐵 ) = 𝑥𝐴 ( 𝐶𝐵 ) )

Proof

Step Hyp Ref Expression
1 iinin1 ( 𝐴 ≠ ∅ → 𝑥𝐴 ( 𝐶𝐵 ) = ( 𝑥𝐴 𝐶𝐵 ) )
2 1 eqcomd ( 𝐴 ≠ ∅ → ( 𝑥𝐴 𝐶𝐵 ) = 𝑥𝐴 ( 𝐶𝐵 ) )