Theorem in3

Description: The virtual deduction introduction rule of converting the end virtual hypothesis of 3 virtual hypotheses into an antecedent. (Contributed by Alan Sare, 12-Jun-2011) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Hypothesis	in3.1	⊢ (    𝜑    ,    𝜓    ,    𝜒    ▶    𝜃    )
Assertion	in3	⊢ (    𝜑    ,    𝜓    ▶    ( 𝜒 → 𝜃 )    )

Proof

Step	Hyp	Ref	Expression
1		in3.1	⊢ (    𝜑    ,    𝜓    ,    𝜒    ▶    𝜃    )
2	1	dfvd3i	⊢ ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜃 ) ) )
3	2	dfvd2ir	⊢ (    𝜑    ,    𝜓    ▶    ( 𝜒 → 𝜃 )    )