| Step | Hyp | Ref | Expression | 
						
							| 1 |  | f1f | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  𝐹 : 𝐴 ⟶ 𝐵 ) | 
						
							| 2 |  | fo2ndf | ⊢ ( 𝐹 : 𝐴 ⟶ 𝐵  →  ( 2nd   ↾  𝐹 ) : 𝐹 –onto→ ran  𝐹 ) | 
						
							| 3 | 1 2 | syl | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( 2nd   ↾  𝐹 ) : 𝐹 –onto→ ran  𝐹 ) | 
						
							| 4 |  | f2ndf | ⊢ ( 𝐹 : 𝐴 ⟶ 𝐵  →  ( 2nd   ↾  𝐹 ) : 𝐹 ⟶ 𝐵 ) | 
						
							| 5 | 1 4 | syl | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( 2nd   ↾  𝐹 ) : 𝐹 ⟶ 𝐵 ) | 
						
							| 6 |  | fssxp | ⊢ ( 𝐹 : 𝐴 ⟶ 𝐵  →  𝐹  ⊆  ( 𝐴  ×  𝐵 ) ) | 
						
							| 7 | 1 6 | syl | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  𝐹  ⊆  ( 𝐴  ×  𝐵 ) ) | 
						
							| 8 |  | ssel2 | ⊢ ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  𝑥  ∈  𝐹 )  →  𝑥  ∈  ( 𝐴  ×  𝐵 ) ) | 
						
							| 9 |  | elxp2 | ⊢ ( 𝑥  ∈  ( 𝐴  ×  𝐵 )  ↔  ∃ 𝑎  ∈  𝐴 ∃ 𝑣  ∈  𝐵 𝑥  =  〈 𝑎 ,  𝑣 〉 ) | 
						
							| 10 | 8 9 | sylib | ⊢ ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  𝑥  ∈  𝐹 )  →  ∃ 𝑎  ∈  𝐴 ∃ 𝑣  ∈  𝐵 𝑥  =  〈 𝑎 ,  𝑣 〉 ) | 
						
							| 11 |  | ssel2 | ⊢ ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  𝑦  ∈  𝐹 )  →  𝑦  ∈  ( 𝐴  ×  𝐵 ) ) | 
						
							| 12 |  | elxp2 | ⊢ ( 𝑦  ∈  ( 𝐴  ×  𝐵 )  ↔  ∃ 𝑏  ∈  𝐴 ∃ 𝑤  ∈  𝐵 𝑦  =  〈 𝑏 ,  𝑤 〉 ) | 
						
							| 13 | 11 12 | sylib | ⊢ ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  𝑦  ∈  𝐹 )  →  ∃ 𝑏  ∈  𝐴 ∃ 𝑤  ∈  𝐵 𝑦  =  〈 𝑏 ,  𝑤 〉 ) | 
						
							| 14 | 10 13 | anim12dan | ⊢ ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 ) )  →  ( ∃ 𝑎  ∈  𝐴 ∃ 𝑣  ∈  𝐵 𝑥  =  〈 𝑎 ,  𝑣 〉  ∧  ∃ 𝑏  ∈  𝐴 ∃ 𝑤  ∈  𝐵 𝑦  =  〈 𝑏 ,  𝑤 〉 ) ) | 
						
							| 15 |  | fvres | ⊢ ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  →  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( 2nd  ‘ 〈 𝑎 ,  𝑣 〉 ) ) | 
						
							| 16 | 15 | ad2antrr | ⊢ ( ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( 2nd  ‘ 〈 𝑎 ,  𝑣 〉 ) ) | 
						
							| 17 |  | fvres | ⊢ ( 〈 𝑏 ,  𝑤 〉  ∈  𝐹  →  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  =  ( 2nd  ‘ 〈 𝑏 ,  𝑤 〉 ) ) | 
						
							| 18 | 17 | ad2antlr | ⊢ ( ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  =  ( 2nd  ‘ 〈 𝑏 ,  𝑤 〉 ) ) | 
						
							| 19 | 16 18 | eqeq12d | ⊢ ( ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  ↔  ( 2nd  ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( 2nd  ‘ 〈 𝑏 ,  𝑤 〉 ) ) ) | 
						
							| 20 |  | vex | ⊢ 𝑎  ∈  V | 
						
							| 21 |  | vex | ⊢ 𝑣  ∈  V | 
						
							| 22 | 20 21 | op2nd | ⊢ ( 2nd  ‘ 〈 𝑎 ,  𝑣 〉 )  =  𝑣 | 
						
							| 23 |  | vex | ⊢ 𝑏  ∈  V | 
						
							| 24 |  | vex | ⊢ 𝑤  ∈  V | 
						
							| 25 | 23 24 | op2nd | ⊢ ( 2nd  ‘ 〈 𝑏 ,  𝑤 〉 )  =  𝑤 | 
						
							| 26 | 22 25 | eqeq12i | ⊢ ( ( 2nd  ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( 2nd  ‘ 〈 𝑏 ,  𝑤 〉 )  ↔  𝑣  =  𝑤 ) | 
						
							| 27 |  | f1fun | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  Fun  𝐹 ) | 
						
							| 28 |  | funopfv | ⊢ ( Fun  𝐹  →  ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  →  ( 𝐹 ‘ 𝑎 )  =  𝑣 ) ) | 
						
							| 29 |  | funopfv | ⊢ ( Fun  𝐹  →  ( 〈 𝑏 ,  𝑤 〉  ∈  𝐹  →  ( 𝐹 ‘ 𝑏 )  =  𝑤 ) ) | 
						
							| 30 | 28 29 | anim12d | ⊢ ( Fun  𝐹  →  ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  →  ( ( 𝐹 ‘ 𝑎 )  =  𝑣  ∧  ( 𝐹 ‘ 𝑏 )  =  𝑤 ) ) ) | 
						
							| 31 | 27 30 | syl | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  →  ( ( 𝐹 ‘ 𝑎 )  =  𝑣  ∧  ( 𝐹 ‘ 𝑏 )  =  𝑤 ) ) ) | 
						
							| 32 |  | eqcom | ⊢ ( ( 𝐹 ‘ 𝑎 )  =  𝑣  ↔  𝑣  =  ( 𝐹 ‘ 𝑎 ) ) | 
						
							| 33 | 32 | biimpi | ⊢ ( ( 𝐹 ‘ 𝑎 )  =  𝑣  →  𝑣  =  ( 𝐹 ‘ 𝑎 ) ) | 
						
							| 34 |  | eqcom | ⊢ ( ( 𝐹 ‘ 𝑏 )  =  𝑤  ↔  𝑤  =  ( 𝐹 ‘ 𝑏 ) ) | 
						
							| 35 | 34 | biimpi | ⊢ ( ( 𝐹 ‘ 𝑏 )  =  𝑤  →  𝑤  =  ( 𝐹 ‘ 𝑏 ) ) | 
						
							| 36 | 33 35 | eqeqan12d | ⊢ ( ( ( 𝐹 ‘ 𝑎 )  =  𝑣  ∧  ( 𝐹 ‘ 𝑏 )  =  𝑤 )  →  ( 𝑣  =  𝑤  ↔  ( 𝐹 ‘ 𝑎 )  =  ( 𝐹 ‘ 𝑏 ) ) ) | 
						
							| 37 |  | simpl | ⊢ ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  →  𝑎  ∈  𝐴 ) | 
						
							| 38 |  | simpl | ⊢ ( ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 )  →  𝑏  ∈  𝐴 ) | 
						
							| 39 | 37 38 | anim12i | ⊢ ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( 𝑎  ∈  𝐴  ∧  𝑏  ∈  𝐴 ) ) | 
						
							| 40 |  | f1veqaeq | ⊢ ( ( 𝐹 : 𝐴 –1-1→ 𝐵  ∧  ( 𝑎  ∈  𝐴  ∧  𝑏  ∈  𝐴 ) )  →  ( ( 𝐹 ‘ 𝑎 )  =  ( 𝐹 ‘ 𝑏 )  →  𝑎  =  𝑏 ) ) | 
						
							| 41 | 39 40 | sylan2 | ⊢ ( ( 𝐹 : 𝐴 –1-1→ 𝐵  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( ( 𝐹 ‘ 𝑎 )  =  ( 𝐹 ‘ 𝑏 )  →  𝑎  =  𝑏 ) ) | 
						
							| 42 |  | opeq12 | ⊢ ( ( 𝑎  =  𝑏  ∧  𝑣  =  𝑤 )  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) | 
						
							| 43 | 42 | ex | ⊢ ( 𝑎  =  𝑏  →  ( 𝑣  =  𝑤  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) | 
						
							| 44 | 41 43 | syl6 | ⊢ ( ( 𝐹 : 𝐴 –1-1→ 𝐵  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( ( 𝐹 ‘ 𝑎 )  =  ( 𝐹 ‘ 𝑏 )  →  ( 𝑣  =  𝑤  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) | 
						
							| 45 | 44 | com23 | ⊢ ( ( 𝐹 : 𝐴 –1-1→ 𝐵  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( 𝑣  =  𝑤  →  ( ( 𝐹 ‘ 𝑎 )  =  ( 𝐹 ‘ 𝑏 )  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) | 
						
							| 46 | 45 | ex | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( 𝑣  =  𝑤  →  ( ( 𝐹 ‘ 𝑎 )  =  ( 𝐹 ‘ 𝑏 )  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 47 | 46 | com14 | ⊢ ( ( 𝐹 ‘ 𝑎 )  =  ( 𝐹 ‘ 𝑏 )  →  ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( 𝑣  =  𝑤  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 48 | 36 47 | biimtrdi | ⊢ ( ( ( 𝐹 ‘ 𝑎 )  =  𝑣  ∧  ( 𝐹 ‘ 𝑏 )  =  𝑤 )  →  ( 𝑣  =  𝑤  →  ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( 𝑣  =  𝑤  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) ) | 
						
							| 49 | 48 | com14 | ⊢ ( 𝑣  =  𝑤  →  ( 𝑣  =  𝑤  →  ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( ( ( 𝐹 ‘ 𝑎 )  =  𝑣  ∧  ( 𝐹 ‘ 𝑏 )  =  𝑤 )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) ) | 
						
							| 50 | 49 | pm2.43i | ⊢ ( 𝑣  =  𝑤  →  ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( ( ( 𝐹 ‘ 𝑎 )  =  𝑣  ∧  ( 𝐹 ‘ 𝑏 )  =  𝑤 )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 51 | 50 | com14 | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( ( ( 𝐹 ‘ 𝑎 )  =  𝑣  ∧  ( 𝐹 ‘ 𝑏 )  =  𝑤 )  →  ( 𝑣  =  𝑤  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 52 | 51 | com23 | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 𝐹 ‘ 𝑎 )  =  𝑣  ∧  ( 𝐹 ‘ 𝑏 )  =  𝑤 )  →  ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( 𝑣  =  𝑤  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 53 | 31 52 | syld | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  →  ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( 𝑣  =  𝑤  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 54 | 53 | com13 | ⊢ ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( 𝑣  =  𝑤  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 55 | 54 | impcom | ⊢ ( ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( 𝑣  =  𝑤  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) | 
						
							| 56 | 55 | com23 | ⊢ ( ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( 𝑣  =  𝑤  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) | 
						
							| 57 | 26 56 | biimtrid | ⊢ ( ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( ( 2nd  ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( 2nd  ‘ 〈 𝑏 ,  𝑤 〉 )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) | 
						
							| 58 | 19 57 | sylbid | ⊢ ( ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) | 
						
							| 59 | 58 | com23 | ⊢ ( ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  ∧  ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) | 
						
							| 60 | 59 | ex | ⊢ ( ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 )  →  ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 61 | 60 | adantl | ⊢ ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 ) )  →  ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 62 | 61 | com12 | ⊢ ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 63 | 62 | ad4ant13 | ⊢ ( ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  ∧  𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 64 |  | eleq1 | ⊢ ( 𝑥  =  〈 𝑎 ,  𝑣 〉  →  ( 𝑥  ∈  𝐹  ↔  〈 𝑎 ,  𝑣 〉  ∈  𝐹 ) ) | 
						
							| 65 | 64 | ad2antlr | ⊢ ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( 𝑥  ∈  𝐹  ↔  〈 𝑎 ,  𝑣 〉  ∈  𝐹 ) ) | 
						
							| 66 |  | eleq1 | ⊢ ( 𝑦  =  〈 𝑏 ,  𝑤 〉  →  ( 𝑦  ∈  𝐹  ↔  〈 𝑏 ,  𝑤 〉  ∈  𝐹 ) ) | 
						
							| 67 | 65 66 | bi2anan9 | ⊢ ( ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  ∧  𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  ( ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 )  ↔  ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 ) ) ) | 
						
							| 68 | 67 | anbi2d | ⊢ ( ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  ∧  𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 ) )  ↔  ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 〈 𝑎 ,  𝑣 〉  ∈  𝐹  ∧  〈 𝑏 ,  𝑤 〉  ∈  𝐹 ) ) ) ) | 
						
							| 69 |  | fveq2 | ⊢ ( 𝑥  =  〈 𝑎 ,  𝑣 〉  →  ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 ) ) | 
						
							| 70 | 69 | ad2antlr | ⊢ ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 ) ) | 
						
							| 71 |  | fveq2 | ⊢ ( 𝑦  =  〈 𝑏 ,  𝑤 〉  →  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 ) ) | 
						
							| 72 | 70 71 | eqeqan12d | ⊢ ( ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  ∧  𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  ↔  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 ) ) ) | 
						
							| 73 |  | simpllr | ⊢ ( ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  ∧  𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  𝑥  =  〈 𝑎 ,  𝑣 〉 ) | 
						
							| 74 |  | simpr | ⊢ ( ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  ∧  𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  𝑦  =  〈 𝑏 ,  𝑤 〉 ) | 
						
							| 75 | 73 74 | eqeq12d | ⊢ ( ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  ∧  𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  ( 𝑥  =  𝑦  ↔  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) | 
						
							| 76 | 72 75 | imbi12d | ⊢ ( ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  ∧  𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  ( ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 )  ↔  ( ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) | 
						
							| 77 | 76 | imbi2d | ⊢ ( ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  ∧  𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  ( ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) )  ↔  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑎 ,  𝑣 〉 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 〈 𝑏 ,  𝑤 〉 )  →  〈 𝑎 ,  𝑣 〉  =  〈 𝑏 ,  𝑤 〉 ) ) ) ) | 
						
							| 78 | 63 68 77 | 3imtr4d | ⊢ ( ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  ∧  𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) ) | 
						
							| 79 | 78 | ex | ⊢ ( ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  ∧  ( 𝑏  ∈  𝐴  ∧  𝑤  ∈  𝐵 ) )  →  ( 𝑦  =  〈 𝑏 ,  𝑤 〉  →  ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) ) ) | 
						
							| 80 | 79 | rexlimdvva | ⊢ ( ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  ∧  𝑥  =  〈 𝑎 ,  𝑣 〉 )  →  ( ∃ 𝑏  ∈  𝐴 ∃ 𝑤  ∈  𝐵 𝑦  =  〈 𝑏 ,  𝑤 〉  →  ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) ) ) | 
						
							| 81 | 80 | ex | ⊢ ( ( 𝑎  ∈  𝐴  ∧  𝑣  ∈  𝐵 )  →  ( 𝑥  =  〈 𝑎 ,  𝑣 〉  →  ( ∃ 𝑏  ∈  𝐴 ∃ 𝑤  ∈  𝐵 𝑦  =  〈 𝑏 ,  𝑤 〉  →  ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) ) ) ) | 
						
							| 82 | 81 | rexlimivv | ⊢ ( ∃ 𝑎  ∈  𝐴 ∃ 𝑣  ∈  𝐵 𝑥  =  〈 𝑎 ,  𝑣 〉  →  ( ∃ 𝑏  ∈  𝐴 ∃ 𝑤  ∈  𝐵 𝑦  =  〈 𝑏 ,  𝑤 〉  →  ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) ) ) | 
						
							| 83 | 82 | imp | ⊢ ( ( ∃ 𝑎  ∈  𝐴 ∃ 𝑣  ∈  𝐵 𝑥  =  〈 𝑎 ,  𝑣 〉  ∧  ∃ 𝑏  ∈  𝐴 ∃ 𝑤  ∈  𝐵 𝑦  =  〈 𝑏 ,  𝑤 〉 )  →  ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) ) | 
						
							| 84 | 14 83 | mpcom | ⊢ ( ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  ∧  ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 ) )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) | 
						
							| 85 | 84 | ex | ⊢ ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  →  ( ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) ) | 
						
							| 86 | 85 | com23 | ⊢ ( 𝐹  ⊆  ( 𝐴  ×  𝐵 )  →  ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 )  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) ) | 
						
							| 87 | 7 86 | mpcom | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( ( 𝑥  ∈  𝐹  ∧  𝑦  ∈  𝐹 )  →  ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) | 
						
							| 88 | 87 | ralrimivv | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ∀ 𝑥  ∈  𝐹 ∀ 𝑦  ∈  𝐹 ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) | 
						
							| 89 |  | dff13 | ⊢ ( ( 2nd   ↾  𝐹 ) : 𝐹 –1-1→ 𝐵  ↔  ( ( 2nd   ↾  𝐹 ) : 𝐹 ⟶ 𝐵  ∧  ∀ 𝑥  ∈  𝐹 ∀ 𝑦  ∈  𝐹 ( ( ( 2nd   ↾  𝐹 ) ‘ 𝑥 )  =  ( ( 2nd   ↾  𝐹 ) ‘ 𝑦 )  →  𝑥  =  𝑦 ) ) ) | 
						
							| 90 | 5 88 89 | sylanbrc | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( 2nd   ↾  𝐹 ) : 𝐹 –1-1→ 𝐵 ) | 
						
							| 91 |  | df-f1 | ⊢ ( ( 2nd   ↾  𝐹 ) : 𝐹 –1-1→ 𝐵  ↔  ( ( 2nd   ↾  𝐹 ) : 𝐹 ⟶ 𝐵  ∧  Fun  ◡ ( 2nd   ↾  𝐹 ) ) ) | 
						
							| 92 | 91 | simprbi | ⊢ ( ( 2nd   ↾  𝐹 ) : 𝐹 –1-1→ 𝐵  →  Fun  ◡ ( 2nd   ↾  𝐹 ) ) | 
						
							| 93 | 90 92 | syl | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  Fun  ◡ ( 2nd   ↾  𝐹 ) ) | 
						
							| 94 |  | dff1o3 | ⊢ ( ( 2nd   ↾  𝐹 ) : 𝐹 –1-1-onto→ ran  𝐹  ↔  ( ( 2nd   ↾  𝐹 ) : 𝐹 –onto→ ran  𝐹  ∧  Fun  ◡ ( 2nd   ↾  𝐹 ) ) ) | 
						
							| 95 | 3 93 94 | sylanbrc | ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵  →  ( 2nd   ↾  𝐹 ) : 𝐹 –1-1-onto→ ran  𝐹 ) |