| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							cvrletr.b | 
							⊢ 𝐵  =  ( Base ‘ 𝐾 )  | 
						
						
							| 2 | 
							
								
							 | 
							cvrletr.l | 
							⊢  ≤   =  ( le ‘ 𝐾 )  | 
						
						
							| 3 | 
							
								
							 | 
							cvrletr.s | 
							⊢  <   =  ( lt ‘ 𝐾 )  | 
						
						
							| 4 | 
							
								
							 | 
							cvrletr.c | 
							⊢ 𝐶  =  (  ⋖  ‘ 𝐾 )  | 
						
						
							| 5 | 
							
								1 3 4
							 | 
							cvrval | 
							⊢ ( ( 𝐾  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  →  ( 𝑋 𝐶 𝑌  ↔  ( 𝑋  <  𝑌  ∧  ¬  ∃ 𝑧  ∈  𝐵 ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 ) ) ) )  | 
						
						
							| 6 | 
							
								
							 | 
							iman | 
							⊢ ( ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  →  𝑧  =  𝑌 )  ↔  ¬  ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  ∧  ¬  𝑧  =  𝑌 ) )  | 
						
						
							| 7 | 
							
								
							 | 
							df-ne | 
							⊢ ( 𝑧  ≠  𝑌  ↔  ¬  𝑧  =  𝑌 )  | 
						
						
							| 8 | 
							
								7
							 | 
							anbi2i | 
							⊢ ( ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  ∧  𝑧  ≠  𝑌 )  ↔  ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  ∧  ¬  𝑧  =  𝑌 ) )  | 
						
						
							| 9 | 
							
								6 8
							 | 
							xchbinxr | 
							⊢ ( ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  →  𝑧  =  𝑌 )  ↔  ¬  ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  ∧  𝑧  ≠  𝑌 ) )  | 
						
						
							| 10 | 
							
								
							 | 
							anass | 
							⊢ ( ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  ∧  𝑧  ≠  𝑌 )  ↔  ( 𝑋  <  𝑧  ∧  ( 𝑧  ≤  𝑌  ∧  𝑧  ≠  𝑌 ) ) )  | 
						
						
							| 11 | 
							
								2 3
							 | 
							pltval | 
							⊢ ( ( 𝐾  ∈  𝐴  ∧  𝑧  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  →  ( 𝑧  <  𝑌  ↔  ( 𝑧  ≤  𝑌  ∧  𝑧  ≠  𝑌 ) ) )  | 
						
						
							| 12 | 
							
								11
							 | 
							3com23 | 
							⊢ ( ( 𝐾  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝑧  ∈  𝐵 )  →  ( 𝑧  <  𝑌  ↔  ( 𝑧  ≤  𝑌  ∧  𝑧  ≠  𝑌 ) ) )  | 
						
						
							| 13 | 
							
								12
							 | 
							3expa | 
							⊢ ( ( ( 𝐾  ∈  𝐴  ∧  𝑌  ∈  𝐵 )  ∧  𝑧  ∈  𝐵 )  →  ( 𝑧  <  𝑌  ↔  ( 𝑧  ≤  𝑌  ∧  𝑧  ≠  𝑌 ) ) )  | 
						
						
							| 14 | 
							
								13
							 | 
							anbi2d | 
							⊢ ( ( ( 𝐾  ∈  𝐴  ∧  𝑌  ∈  𝐵 )  ∧  𝑧  ∈  𝐵 )  →  ( ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 )  ↔  ( 𝑋  <  𝑧  ∧  ( 𝑧  ≤  𝑌  ∧  𝑧  ≠  𝑌 ) ) ) )  | 
						
						
							| 15 | 
							
								10 14
							 | 
							bitr4id | 
							⊢ ( ( ( 𝐾  ∈  𝐴  ∧  𝑌  ∈  𝐵 )  ∧  𝑧  ∈  𝐵 )  →  ( ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  ∧  𝑧  ≠  𝑌 )  ↔  ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 ) ) )  | 
						
						
							| 16 | 
							
								15
							 | 
							notbid | 
							⊢ ( ( ( 𝐾  ∈  𝐴  ∧  𝑌  ∈  𝐵 )  ∧  𝑧  ∈  𝐵 )  →  ( ¬  ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  ∧  𝑧  ≠  𝑌 )  ↔  ¬  ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 ) ) )  | 
						
						
							| 17 | 
							
								9 16
							 | 
							bitrid | 
							⊢ ( ( ( 𝐾  ∈  𝐴  ∧  𝑌  ∈  𝐵 )  ∧  𝑧  ∈  𝐵 )  →  ( ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  →  𝑧  =  𝑌 )  ↔  ¬  ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 ) ) )  | 
						
						
							| 18 | 
							
								17
							 | 
							ralbidva | 
							⊢ ( ( 𝐾  ∈  𝐴  ∧  𝑌  ∈  𝐵 )  →  ( ∀ 𝑧  ∈  𝐵 ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  →  𝑧  =  𝑌 )  ↔  ∀ 𝑧  ∈  𝐵 ¬  ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 ) ) )  | 
						
						
							| 19 | 
							
								
							 | 
							ralnex | 
							⊢ ( ∀ 𝑧  ∈  𝐵 ¬  ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 )  ↔  ¬  ∃ 𝑧  ∈  𝐵 ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 ) )  | 
						
						
							| 20 | 
							
								18 19
							 | 
							bitrdi | 
							⊢ ( ( 𝐾  ∈  𝐴  ∧  𝑌  ∈  𝐵 )  →  ( ∀ 𝑧  ∈  𝐵 ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  →  𝑧  =  𝑌 )  ↔  ¬  ∃ 𝑧  ∈  𝐵 ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 ) ) )  | 
						
						
							| 21 | 
							
								20
							 | 
							anbi2d | 
							⊢ ( ( 𝐾  ∈  𝐴  ∧  𝑌  ∈  𝐵 )  →  ( ( 𝑋  <  𝑌  ∧  ∀ 𝑧  ∈  𝐵 ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  →  𝑧  =  𝑌 ) )  ↔  ( 𝑋  <  𝑌  ∧  ¬  ∃ 𝑧  ∈  𝐵 ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 ) ) ) )  | 
						
						
							| 22 | 
							
								21
							 | 
							3adant2 | 
							⊢ ( ( 𝐾  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  →  ( ( 𝑋  <  𝑌  ∧  ∀ 𝑧  ∈  𝐵 ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  →  𝑧  =  𝑌 ) )  ↔  ( 𝑋  <  𝑌  ∧  ¬  ∃ 𝑧  ∈  𝐵 ( 𝑋  <  𝑧  ∧  𝑧  <  𝑌 ) ) ) )  | 
						
						
							| 23 | 
							
								5 22
							 | 
							bitr4d | 
							⊢ ( ( 𝐾  ∈  𝐴  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 )  →  ( 𝑋 𝐶 𝑌  ↔  ( 𝑋  <  𝑌  ∧  ∀ 𝑧  ∈  𝐵 ( ( 𝑋  <  𝑧  ∧  𝑧  ≤  𝑌 )  →  𝑧  =  𝑌 ) ) ) )  |