Metamath Proof Explorer


Theorem dfvd3an

Description: Definition of a 3-hypothesis virtual deduction in vd conjunction form. (Contributed by Alan Sare, 13-Jun-2015) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Assertion dfvd3an ( (    (    𝜑    ,    𝜓    ,    𝜒    )    ▶    𝜃    ) ↔ ( ( 𝜑𝜓𝜒 ) → 𝜃 ) )

Proof

Step Hyp Ref Expression
1 df-vd1 ( (    (    𝜑    ,    𝜓    ,    𝜒    )    ▶    𝜃    ) ↔ ( (    𝜑    ,    𝜓    ,    𝜒    )𝜃 ) )
2 df-vhc3 ( (    𝜑    ,    𝜓    ,    𝜒    ) ↔ ( 𝜑𝜓𝜒 ) )
3 2 imbi1i ( ( (    𝜑    ,    𝜓    ,    𝜒    )𝜃 ) ↔ ( ( 𝜑𝜓𝜒 ) → 𝜃 ) )
4 1 3 bitri ( (    (    𝜑    ,    𝜓    ,    𝜒    )    ▶    𝜃    ) ↔ ( ( 𝜑𝜓𝜒 ) → 𝜃 ) )