Metamath Proof Explorer


Theorem exbiriVD

Description: Virtual deduction proof of exbiri . The following user's proof is completed by invoking mmj2's unify command and using mmj2's StepSelector to pick all remaining steps of the Metamath proof.

h1:: |- ( ( ph /\ ps ) -> ( ch <-> th ) )
2:: |- (. ph ->. ph ).
3:: |- (. ph ,. ps ->. ps ).
4:: |- (. ph ,. ps ,. th ->. th ).
5:2,1,?: e10 |- (. ph ->. ( ps -> ( ch <-> th ) ) ).
6:3,5,?: e21 |- (. ph ,. ps ->. ( ch <-> th ) ).
7:4,6,?: e32 |- (. ph ,. ps ,. th ->. ch ).
8:7: |- (. ph ,. ps ->. ( th -> ch ) ).
9:8: |- (. ph ->. ( ps -> ( th -> ch ) ) ).
qed:9: |- ( ph -> ( ps -> ( th -> ch ) ) )
(Contributed by Alan Sare, 31-Dec-2011) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Hypothesis exbiriVD.1 ( ( 𝜑𝜓 ) → ( 𝜒𝜃 ) )
Assertion exbiriVD ( 𝜑 → ( 𝜓 → ( 𝜃𝜒 ) ) )

Proof

Step Hyp Ref Expression
1 exbiriVD.1 ( ( 𝜑𝜓 ) → ( 𝜒𝜃 ) )
2 idn3 (    𝜑    ,    𝜓    ,    𝜃    ▶    𝜃    )
3 idn2 (    𝜑    ,    𝜓    ▶    𝜓    )
4 idn1 (    𝜑    ▶    𝜑    )
5 pm3.3 ( ( ( 𝜑𝜓 ) → ( 𝜒𝜃 ) ) → ( 𝜑 → ( 𝜓 → ( 𝜒𝜃 ) ) ) )
6 5 com12 ( 𝜑 → ( ( ( 𝜑𝜓 ) → ( 𝜒𝜃 ) ) → ( 𝜓 → ( 𝜒𝜃 ) ) ) )
7 4 1 6 e10 (    𝜑    ▶    ( 𝜓 → ( 𝜒𝜃 ) )    )
8 pm2.27 ( 𝜓 → ( ( 𝜓 → ( 𝜒𝜃 ) ) → ( 𝜒𝜃 ) ) )
9 3 7 8 e21 (    𝜑    ,    𝜓    ▶    ( 𝜒𝜃 )    )
10 biimpr ( ( 𝜒𝜃 ) → ( 𝜃𝜒 ) )
11 10 com12 ( 𝜃 → ( ( 𝜒𝜃 ) → 𝜒 ) )
12 2 9 11 e32 (    𝜑    ,    𝜓    ,    𝜃    ▶    𝜒    )
13 12 in3 (    𝜑    ,    𝜓    ▶    ( 𝜃𝜒 )    )
14 13 in2 (    𝜑    ▶    ( 𝜓 → ( 𝜃𝜒 ) )    )
15 14 in1 ( 𝜑 → ( 𝜓 → ( 𝜃𝜒 ) ) )