Metamath Proof Explorer


Theorem disjeqi

Description: Equality theorem for disjoints, inference version. (Contributed by Peter Mazsa, 22-Sep-2021)

Ref Expression
Hypothesis disjeqi.1 𝐴 = 𝐵
Assertion disjeqi ( Disj 𝐴 ↔ Disj 𝐵 )

Proof

Step Hyp Ref Expression
1 disjeqi.1 𝐴 = 𝐵
2 disjeq ( 𝐴 = 𝐵 → ( Disj 𝐴 ↔ Disj 𝐵 ) )
3 1 2 ax-mp ( Disj 𝐴 ↔ Disj 𝐵 )