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