Metamath Proof Explorer


Theorem djurf1o

Description: The right injection function on all sets is one to one and onto. (Contributed by Jim Kingdon, 22-Jun-2022)

Ref Expression
Assertion djurf1o inr : V –1-1-onto→ ( { 1o } × V )

Proof

Step Hyp Ref Expression
1 df-inr ⊢ inr = ( 𝑥 ∈ V ↦ ⟨ 1o , 𝑥 ⟩ )
2 1onn ⊢ 1o ∈ ω
3 snidg ⊢ ( 1o ∈ ω → 1o ∈ { 1o } )
4 2 3 ax-mp ⊢ 1o ∈ { 1o }
5 opelxpi ⊢ ( ( 1o ∈ { 1o } ∧ 𝑥 ∈ V ) → ⟨ 1o , 𝑥 ⟩ ∈ ( { 1o } × V ) )
6 4 5 mpan ⊢ ( 𝑥 ∈ V → ⟨ 1o , 𝑥 ⟩ ∈ ( { 1o } × V ) )
7 6 adantl ⊢ ( ( ⊤ ∧ 𝑥 ∈ V ) → ⟨ 1o , 𝑥 ⟩ ∈ ( { 1o } × V ) )
8 fvexd ⊢ ( ( ⊤ ∧ 𝑦 ∈ ( { 1o } × V ) ) → ( 2nd ‘ 𝑦 ) ∈ V )
9 1st2nd2 ⊢ ( 𝑦 ∈ ( { 1o } × V ) → 𝑦 = ⟨ ( 1st ‘ 𝑦 ) , ( 2nd ‘ 𝑦 ) ⟩ )
10 xp1st ⊢ ( 𝑦 ∈ ( { 1o } × V ) → ( 1st ‘ 𝑦 ) ∈ { 1o } )
11 elsni ⊢ ( ( 1st ‘ 𝑦 ) ∈ { 1o } → ( 1st ‘ 𝑦 ) = 1o )
12 10 11 syl ⊢ ( 𝑦 ∈ ( { 1o } × V ) → ( 1st ‘ 𝑦 ) = 1o )
13 12 opeq1d ⊢ ( 𝑦 ∈ ( { 1o } × V ) → ⟨ ( 1st ‘ 𝑦 ) , ( 2nd ‘ 𝑦 ) ⟩ = ⟨ 1o , ( 2nd ‘ 𝑦 ) ⟩ )
14 9 13 eqtrd ⊢ ( 𝑦 ∈ ( { 1o } × V ) → 𝑦 = ⟨ 1o , ( 2nd ‘ 𝑦 ) ⟩ )
15 14 eqeq2d ⊢ ( 𝑦 ∈ ( { 1o } × V ) → ( ⟨ 1o , 𝑥 ⟩ = 𝑦 ↔ ⟨ 1o , 𝑥 ⟩ = ⟨ 1o , ( 2nd ‘ 𝑦 ) ⟩ ) )
16 eqcom ⊢ ( ⟨ 1o , 𝑥 ⟩ = 𝑦 ↔ 𝑦 = ⟨ 1o , 𝑥 ⟩ )
17 eqid ⊢ 1o = 1o
18 1oex ⊢ 1o ∈ V
19 vex ⊢ 𝑥 ∈ V
20 18 19 opth ⊢ ( ⟨ 1o , 𝑥 ⟩ = ⟨ 1o , ( 2nd ‘ 𝑦 ) ⟩ ↔ ( 1o = 1o ∧ 𝑥 = ( 2nd ‘ 𝑦 ) ) )
21 17 20 mpbiran ⊢ ( ⟨ 1o , 𝑥 ⟩ = ⟨ 1o , ( 2nd ‘ 𝑦 ) ⟩ ↔ 𝑥 = ( 2nd ‘ 𝑦 ) )
22 15 16 21 3bitr3g ⊢ ( 𝑦 ∈ ( { 1o } × V ) → ( 𝑦 = ⟨ 1o , 𝑥 ⟩ ↔ 𝑥 = ( 2nd ‘ 𝑦 ) ) )
23 22 bicomd ⊢ ( 𝑦 ∈ ( { 1o } × V ) → ( 𝑥 = ( 2nd ‘ 𝑦 ) ↔ 𝑦 = ⟨ 1o , 𝑥 ⟩ ) )
24 23 ad2antll ⊢ ( ( ⊤ ∧ ( 𝑥 ∈ V ∧ 𝑦 ∈ ( { 1o } × V ) ) ) → ( 𝑥 = ( 2nd ‘ 𝑦 ) ↔ 𝑦 = ⟨ 1o , 𝑥 ⟩ ) )
25 1 7 8 24 f1o2d ⊢ ( ⊤ → inr : V –1-1-onto→ ( { 1o } × V ) )
26 25 mptru ⊢ inr : V –1-1-onto→ ( { 1o } × V )