Metamath Proof Explorer


Theorem iineq2dv

Description: Equality deduction for indexed intersection. (Contributed by NM, 3-Aug-2004)

Ref Expression
Hypothesis iuneq2dv.1 ⊢ φ ∧ x ∈ A → B = C
Assertion iineq2dv ⊢ φ → ⋂ x ∈ A B = ⋂ x ∈ A C

Proof

Step Hyp Ref Expression
1 iuneq2dv.1 ⊢ φ ∧ x ∈ A → B = C
2 1 ralrimiva ⊢ φ → ∀ x ∈ A B = C
3 iineq2 ⊢ ∀ x ∈ A B = C → ⋂ x ∈ A B = ⋂ x ∈ A C
4 2 3 syl ⊢ φ → ⋂ x ∈ A B = ⋂ x ∈ A C