Metamath Proof Explorer


Theorem bj-falor2

Description: Dual of truan . (Contributed by BJ, 26-Oct-2019) (Proof modification is discouraged.)

Ref Expression
Assertion bj-falor2 ( ( ⊥ ∨ 𝜑 ) ↔ 𝜑 )

Proof

Step Hyp Ref Expression
1 falim ⊢ ( ⊥ → 𝜑 )
2 1 bj-jaoi1 ⊢ ( ( ⊥ ∨ 𝜑 ) → 𝜑 )
3 olc ⊢ ( 𝜑 → ( ⊥ ∨ 𝜑 ) )
4 2 3 impbii ⊢ ( ( ⊥ ∨ 𝜑 ) ↔ 𝜑 )