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Description: The set of functions between two classes exists if the codomain exists. Generalization of mapex to arbitrary domains. (Contributed by AV, 14-Aug-2024)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | fsetex | ⊢ ( 𝐵 ∈ 𝑉 → { 𝑓 ∣ 𝑓 : 𝐴 ⟶ 𝐵 } ∈ V ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | mapfset | ⊢ ( 𝐵 ∈ 𝑉 → { 𝑓 ∣ 𝑓 : 𝐴 ⟶ 𝐵 } = ( 𝐵 ↑m 𝐴 ) ) | |
| 2 | ovex | ⊢ ( 𝐵 ↑m 𝐴 ) ∈ V | |
| 3 | 1 2 | eqeltrdi | ⊢ ( 𝐵 ∈ 𝑉 → { 𝑓 ∣ 𝑓 : 𝐴 ⟶ 𝐵 } ∈ V ) |