Metamath Proof Explorer


Theorem elriin

Description: Elementhood in a relative intersection. (Contributed by Mario Carneiro, 30-Dec-2016)

Ref Expression
Assertion elriin BAxXSBAxXBS

Proof

Step Hyp Ref Expression
1 elin BAxXSBABxXS
2 eliin BABxXSxXBS
3 2 pm5.32i BABxXSBAxXBS
4 1 3 bitri BAxXSBAxXBS