Metamath Proof Explorer


Theorem eldisjssi

Description: Subclass theorem for disjoint elementhood, inference version. (Contributed by Peter Mazsa, 28-Sep-2021)

Ref Expression
Hypothesis eldisjssi.1 𝐴𝐵
Assertion eldisjssi ( ElDisj 𝐵 → ElDisj 𝐴 )

Proof

Step Hyp Ref Expression
1 eldisjssi.1 𝐴𝐵
2 eldisjss ( 𝐴𝐵 → ( ElDisj 𝐵 → ElDisj 𝐴 ) )
3 1 2 ax-mp ( ElDisj 𝐵 → ElDisj 𝐴 )