Metamath Proof Explorer


Theorem fullfunfv

Description: The function value of the full function of F agrees with F . (Contributed by Scott Fenton, 17-Apr-2014) (Revised by Mario Carneiro, 19-Apr-2014)

Ref Expression
Assertion fullfunfv ⊢ 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ A = F ⁡ A

Proof

Step Hyp Ref Expression
1 fveq2 ⊢ x = A → 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ x = 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ A
2 fveq2 ⊢ x = A → F ⁡ x = F ⁡ A
3 1 2 eqeq12d ⊢ x = A → 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ x = F ⁡ x ↔ 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ A = F ⁡ A
4 df-fullfun ⊢ 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F = 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅
5 4 fveq1i ⊢ 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ x = 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x
6 disjdif ⊢ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∩ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F = ∅
7 funpartfun ⊢ Fun ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F
8 funfn ⊢ Fun ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ↔ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F Fn dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F
9 7 8 mpbi ⊢ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F Fn dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F
10 0ex ⊢ ∅ ∈ V
11 10 fconst ⊢ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ : V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ⟶ ∅
12 ffn ⊢ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ : V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ⟶ ∅ → V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ Fn V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F
13 11 12 ax-mp ⊢ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ Fn V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F
14 fvun1 ⊢ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F Fn dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∧ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ Fn V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∧ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∩ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F = ∅ ∧ x ∈ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ⁡ x
15 9 13 14 mp3an12 ⊢ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∩ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F = ∅ ∧ x ∈ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ⁡ x
16 6 15 mpan ⊢ x ∈ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ⁡ x
17 vex ⊢ x ∈ V
18 eldif ⊢ x ∈ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ↔ x ∈ V ∧ ¬ x ∈ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F
19 17 18 mpbiran ⊢ x ∈ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ↔ ¬ x ∈ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F
20 fvun2 ⊢ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F Fn dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∧ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ Fn V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∧ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∩ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F = ∅ ∧ x ∈ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x
21 9 13 20 mp3an12 ⊢ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∩ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F = ∅ ∧ x ∈ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x
22 6 21 mpan ⊢ x ∈ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x
23 10 fvconst2 ⊢ x ∈ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = ∅
24 22 23 eqtrd ⊢ x ∈ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = ∅
25 19 24 sylbir ⊢ ¬ x ∈ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = ∅
26 ndmfv ⊢ ¬ x ∈ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ⁡ x = ∅
27 25 26 eqtr4d ⊢ ¬ x ∈ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F → 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ⁡ x
28 16 27 pm2.61i ⊢ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ∪ V ∖ dom ⁡ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F × ∅ ⁡ x = 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ⁡ x
29 funpartfv ⊢ 𝖥𝗎𝗇𝖯𝖺𝗋𝗍 F ⁡ x = F ⁡ x
30 5 28 29 3eqtri ⊢ 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ x = F ⁡ x
31 3 30 vtoclg ⊢ A ∈ V → 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ A = F ⁡ A
32 fvprc ⊢ ¬ A ∈ V → 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ A = ∅
33 fvprc ⊢ ¬ A ∈ V → F ⁡ A = ∅
34 32 33 eqtr4d ⊢ ¬ A ∈ V → 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ A = F ⁡ A
35 31 34 pm2.61i ⊢ 𝖥𝗎𝗅𝗅𝖥𝗎𝗇 F ⁡ A = F ⁡ A