Metamath Proof Explorer


Theorem elriin

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

Ref Expression
Assertion elriin B A x X S B A x X B S

Proof

Step Hyp Ref Expression
1 elin B A x X S B A B x X S
2 eliin B A B x X S x X B S
3 2 pm5.32i B A B x X S B A x X B S
4 1 3 bitri B A x X S B A x X B S