Metamath Proof Explorer


Theorem ineqri

Description: Inference from membership to intersection. (Contributed by NM, 21-Jun-1993)

Ref Expression
Hypothesis ineqri.1
|- ( ( x e. A /\ x e. B ) <-> x e. C )
Assertion ineqri
|- ( A i^i B ) = C

Proof

Step Hyp Ref Expression
1 ineqri.1
 |-  ( ( x e. A /\ x e. B ) <-> x e. C )
2 elin
 |-  ( x e. ( A i^i B ) <-> ( x e. A /\ x e. B ) )
3 2 1 bitri
 |-  ( x e. ( A i^i B ) <-> x e. C )
4 3 eqriv
 |-  ( A i^i B ) = C