Theorem ffrnbd 6762

Description: A function maps to its range iff the range is a subset of its codomain. Generalization of ffrn 6760. (Contributed by AV, 20-Sep-2024.)

Hypothesis

Ref	Expression
ffrnbd.r	⊢ (𝜑 → ran 𝐹 ⊆ 𝐵)

Assertion

Ref	Expression
ffrnbd	⊢ (𝜑 → (𝐹:𝐴⟶𝐵 ↔ 𝐹:𝐴⟶ran 𝐹))

Proof of Theorem ffrnbd

Step	Hyp	Ref	Expression
1		ffrnb 6761	. 2 ⊢ (𝐹:𝐴⟶𝐵 ↔ (𝐹:𝐴⟶ran 𝐹 ∧ ran 𝐹 ⊆ 𝐵))
2		ffrnbd.r	. . 3 ⊢ (𝜑 → ran 𝐹 ⊆ 𝐵)
3	2	biantrud 531	. 2 ⊢ (𝜑 → (𝐹:𝐴⟶ran 𝐹 ↔ (𝐹:𝐴⟶ran 𝐹 ∧ ran 𝐹 ⊆ 𝐵)))
4	1, 3	bitr4id 290	1 ⊢ (𝜑 → (𝐹:𝐴⟶𝐵 ↔ 𝐹:𝐴⟶ran 𝐹))

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   ⊆ wss 3976  ran crn 5701  ⟶wf 6569

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1793

This theorem depends on definitions:  df-bi 207  df-an 396  df-ss 3993  df-f 6577

This theorem is referenced by: (None)