This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: If the domain of a function is a set, the function is a set. (Contributed by Glauco Siliprandi, 23-Oct-2021)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | fnexd.1 | ⊢ ( 𝜑 → 𝐹 Fn 𝐴 ) | |
| fnexd.2 | ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 ) | ||
| Assertion | fnexd | ⊢ ( 𝜑 → 𝐹 ∈ V ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | fnexd.1 | ⊢ ( 𝜑 → 𝐹 Fn 𝐴 ) | |
| 2 | fnexd.2 | ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 ) | |
| 3 | fnex | ⊢ ( ( 𝐹 Fn 𝐴 ∧ 𝐴 ∈ 𝑉 ) → 𝐹 ∈ V ) | |
| 4 | 1 2 3 | syl2anc | ⊢ ( 𝜑 → 𝐹 ∈ V ) |