Metamath Proof Explorer


Theorem bnj93

Description: Technical lemma for bnj97 . This lemma may no longer be used or have become an indirect lemma of the theorem in question (i.e. a lemma of a lemma... of the theorem). (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

Ref Expression
Assertion bnj93 ( ( 𝑅 FrSe 𝐴 ∧ 𝑥 ∈ 𝐴 ) → pred ( 𝑥 , 𝐴 , 𝑅 ) ∈ V )

Proof

Step Hyp Ref Expression
1 df-bnj15 ⊢ ( 𝑅 FrSe 𝐴 ↔ ( 𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴 ) )
2 1 simprbi ⊢ ( 𝑅 FrSe 𝐴 → 𝑅 Se 𝐴 )
3 df-bnj13 ⊢ ( 𝑅 Se 𝐴 ↔ ∀ 𝑥 ∈ 𝐴 pred ( 𝑥 , 𝐴 , 𝑅 ) ∈ V )
4 2 3 sylib ⊢ ( 𝑅 FrSe 𝐴 → ∀ 𝑥 ∈ 𝐴 pred ( 𝑥 , 𝐴 , 𝑅 ) ∈ V )
5 4 r19.21bi ⊢ ( ( 𝑅 FrSe 𝐴 ∧ 𝑥 ∈ 𝐴 ) → pred ( 𝑥 , 𝐴 , 𝑅 ) ∈ V )