Metamath Proof Explorer


Theorem sbor2

Description: One direction of sbor , using fewer axioms. Compare 19.33 . (Contributed by Steven Nguyen, 18-Aug-2023)

Ref Expression
Assertion sbor2 ( ( [ 𝑡 / 𝑥 ] 𝜑 ∨ [ 𝑡 / 𝑥 ] 𝜓 ) → [ 𝑡 / 𝑥 ] ( 𝜑𝜓 ) )

Proof

Step Hyp Ref Expression
1 orc ( 𝜑 → ( 𝜑𝜓 ) )
2 1 sbimi ( [ 𝑡 / 𝑥 ] 𝜑 → [ 𝑡 / 𝑥 ] ( 𝜑𝜓 ) )
3 olc ( 𝜓 → ( 𝜑𝜓 ) )
4 3 sbimi ( [ 𝑡 / 𝑥 ] 𝜓 → [ 𝑡 / 𝑥 ] ( 𝜑𝜓 ) )
5 2 4 jaoi ( ( [ 𝑡 / 𝑥 ] 𝜑 ∨ [ 𝑡 / 𝑥 ] 𝜓 ) → [ 𝑡 / 𝑥 ] ( 𝜑𝜓 ) )