| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							ltrnj.b | 
							⊢ 𝐵  =  ( Base ‘ 𝐾 )  | 
						
						
							| 2 | 
							
								
							 | 
							ltrnj.j | 
							⊢  ∨   =  ( join ‘ 𝐾 )  | 
						
						
							| 3 | 
							
								
							 | 
							ltrnj.h | 
							⊢ 𝐻  =  ( LHyp ‘ 𝐾 )  | 
						
						
							| 4 | 
							
								
							 | 
							ltrnj.t | 
							⊢ 𝑇  =  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 )  | 
						
						
							| 5 | 
							
								
							 | 
							simp1l | 
							⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝑇  ∧  ( 𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 ) )  →  𝐾  ∈  HL )  | 
						
						
							| 6 | 
							
								5
							 | 
							hllatd | 
							⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝑇  ∧  ( 𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 ) )  →  𝐾  ∈  Lat )  | 
						
						
							| 7 | 
							
								
							 | 
							eqid | 
							⊢ ( LAut ‘ 𝐾 )  =  ( LAut ‘ 𝐾 )  | 
						
						
							| 8 | 
							
								3 7 4
							 | 
							ltrnlaut | 
							⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝑇 )  →  𝐹  ∈  ( LAut ‘ 𝐾 ) )  | 
						
						
							| 9 | 
							
								8
							 | 
							3adant3 | 
							⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝑇  ∧  ( 𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 ) )  →  𝐹  ∈  ( LAut ‘ 𝐾 ) )  | 
						
						
							| 10 | 
							
								
							 | 
							simp3l | 
							⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝑇  ∧  ( 𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 ) )  →  𝑋  ∈  𝐵 )  | 
						
						
							| 11 | 
							
								
							 | 
							simp3r | 
							⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝑇  ∧  ( 𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 ) )  →  𝑌  ∈  𝐵 )  | 
						
						
							| 12 | 
							
								1 2 7
							 | 
							lautj | 
							⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝐹  ∈  ( LAut ‘ 𝐾 )  ∧  𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 ) )  →  ( 𝐹 ‘ ( 𝑋  ∨  𝑌 ) )  =  ( ( 𝐹 ‘ 𝑋 )  ∨  ( 𝐹 ‘ 𝑌 ) ) )  | 
						
						
							| 13 | 
							
								6 9 10 11 12
							 | 
							syl13anc | 
							⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝑇  ∧  ( 𝑋  ∈  𝐵  ∧  𝑌  ∈  𝐵 ) )  →  ( 𝐹 ‘ ( 𝑋  ∨  𝑌 ) )  =  ( ( 𝐹 ‘ 𝑋 )  ∨  ( 𝐹 ‘ 𝑌 ) ) )  |