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 ) ) | 
| 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 ) ) |