Metamath Proof Explorer


Theorem funexw

Description: Weak version of funex that holds without ax-rep . If the domain and codomain of a function exist, so does the function. (Contributed by Rohan Ridenour, 13-Aug-2023)

Ref Expression
Assertion funexw ( ( Fun 𝐹 ∧ dom 𝐹 ∈ 𝐵 ∧ ran 𝐹 ∈ 𝐶 ) → 𝐹 ∈ V )

Proof

Step Hyp Ref Expression
1 xpexg ⊢ ( ( dom 𝐹 ∈ 𝐵 ∧ ran 𝐹 ∈ 𝐶 ) → ( dom 𝐹 × ran 𝐹 ) ∈ V )
2 1 3adant1 ⊢ ( ( Fun 𝐹 ∧ dom 𝐹 ∈ 𝐵 ∧ ran 𝐹 ∈ 𝐶 ) → ( dom 𝐹 × ran 𝐹 ) ∈ V )
3 funrel ⊢ ( Fun 𝐹 → Rel 𝐹 )
4 relssdmrn ⊢ ( Rel 𝐹 → 𝐹 ⊆ ( dom 𝐹 × ran 𝐹 ) )
5 3 4 syl ⊢ ( Fun 𝐹 → 𝐹 ⊆ ( dom 𝐹 × ran 𝐹 ) )
6 5 3ad2ant1 ⊢ ( ( Fun 𝐹 ∧ dom 𝐹 ∈ 𝐵 ∧ ran 𝐹 ∈ 𝐶 ) → 𝐹 ⊆ ( dom 𝐹 × ran 𝐹 ) )
7 2 6 ssexd ⊢ ( ( Fun 𝐹 ∧ dom 𝐹 ∈ 𝐵 ∧ ran 𝐹 ∈ 𝐶 ) → 𝐹 ∈ V )