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 ) |