Metamath Proof Explorer


Theorem funcsetcestrclem4

Description: Lemma 4 for funcsetcestrc . (Contributed by AV, 27-Mar-2020)

Ref Expression
Hypotheses funcsetcestrc.s ⊢ S = SetCat ⁡ U
funcsetcestrc.c ⊢ C = Base S
funcsetcestrc.f ⊢ φ → F = x ∈ C ⟼ Base ndx x
funcsetcestrc.u ⊢ φ → U ∈ WUni
funcsetcestrc.o ⊢ φ → ω ∈ U
funcsetcestrc.g ⊢ φ → G = x ∈ C , y ∈ C ⟼ I ↾ y x
Assertion funcsetcestrclem4 ⊢ φ → G Fn C × C

Proof

Step Hyp Ref Expression
1 funcsetcestrc.s ⊢ S = SetCat ⁡ U
2 funcsetcestrc.c ⊢ C = Base S
3 funcsetcestrc.f ⊢ φ → F = x ∈ C ⟼ Base ndx x
4 funcsetcestrc.u ⊢ φ → U ∈ WUni
5 funcsetcestrc.o ⊢ φ → ω ∈ U
6 funcsetcestrc.g ⊢ φ → G = x ∈ C , y ∈ C ⟼ I ↾ y x
7 eqid ⊢ x ∈ C , y ∈ C ⟼ I ↾ y x = x ∈ C , y ∈ C ⟼ I ↾ y x
8 ovex ⊢ y x ∈ V
9 resiexg ⊢ y x ∈ V → I ↾ y x ∈ V
10 8 9 ax-mp ⊢ I ↾ y x ∈ V
11 7 10 fnmpoi ⊢ x ∈ C , y ∈ C ⟼ I ↾ y x Fn C × C
12 6 fneq1d ⊢ φ → G Fn C × C ↔ x ∈ C , y ∈ C ⟼ I ↾ y x Fn C × C
13 11 12 mpbiri ⊢ φ → G Fn C × C