Description: Membership in class intersection. (Contributed by Glauco Siliprandi, 3-Jan-2021)
Ref | Expression | ||
---|---|---|---|
Hypotheses | elintdv.1 | ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 ) | |
elintdv.2 | ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐵 ) → 𝐴 ∈ 𝑥 ) | ||
Assertion | elintdv | ⊢ ( 𝜑 → 𝐴 ∈ ∩ 𝐵 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elintdv.1 | ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 ) | |
2 | elintdv.2 | ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐵 ) → 𝐴 ∈ 𝑥 ) | |
3 | nfv | ⊢ Ⅎ 𝑥 𝜑 | |
4 | 3 1 2 | elintd | ⊢ ( 𝜑 → 𝐴 ∈ ∩ 𝐵 ) |