Description: The converse of the binary epsilon relation. (Contributed by Peter Mazsa, 30-Jan-2018)
Ref | Expression | ||
---|---|---|---|
Assertion | brcnvep | ⊢ ( 𝐴 ∈ 𝑉 → ( 𝐴 ◡ E 𝐵 ↔ 𝐵 ∈ 𝐴 ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | rele | ⊢ Rel E | |
2 | 1 | relbrcnv | ⊢ ( 𝐴 ◡ E 𝐵 ↔ 𝐵 E 𝐴 ) |
3 | epelg | ⊢ ( 𝐴 ∈ 𝑉 → ( 𝐵 E 𝐴 ↔ 𝐵 ∈ 𝐴 ) ) | |
4 | 2 3 | syl5bb | ⊢ ( 𝐴 ∈ 𝑉 → ( 𝐴 ◡ E 𝐵 ↔ 𝐵 ∈ 𝐴 ) ) |