| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							cdleme4.l | 
							⊢  ≤   =  ( le ‘ 𝐾 )  | 
						
						
							| 2 | 
							
								
							 | 
							cdleme4.j | 
							⊢  ∨   =  ( join ‘ 𝐾 )  | 
						
						
							| 3 | 
							
								
							 | 
							cdleme4.m | 
							⊢  ∧   =  ( meet ‘ 𝐾 )  | 
						
						
							| 4 | 
							
								
							 | 
							cdleme4.a | 
							⊢ 𝐴  =  ( Atoms ‘ 𝐾 )  | 
						
						
							| 5 | 
							
								
							 | 
							cdleme4.h | 
							⊢ 𝐻  =  ( LHyp ‘ 𝐾 )  | 
						
						
							| 6 | 
							
								
							 | 
							cdleme4.u | 
							⊢ 𝑈  =  ( ( 𝑃  ∨  𝑄 )  ∧  𝑊 )  | 
						
						
							| 7 | 
							
								
							 | 
							cdleme4.f | 
							⊢ 𝐹  =  ( ( 𝑆  ∨  𝑈 )  ∧  ( 𝑄  ∨  ( ( 𝑃  ∨  𝑆 )  ∧  𝑊 ) ) )  | 
						
						
							| 8 | 
							
								
							 | 
							cdleme4.g | 
							⊢ 𝐺  =  ( ( 𝑃  ∨  𝑄 )  ∧  ( 𝐹  ∨  ( ( 𝑅  ∨  𝑆 )  ∧  𝑊 ) ) )  | 
						
						
							| 9 | 
							
								
							 | 
							cdleme7.v | 
							⊢ 𝑉  =  ( ( 𝑅  ∨  𝑆 )  ∧  𝑊 )  | 
						
						
							| 10 | 
							
								9
							 | 
							oveq2i | 
							⊢ ( 𝐹  ∨  𝑉 )  =  ( 𝐹  ∨  ( ( 𝑅  ∨  𝑆 )  ∧  𝑊 ) )  | 
						
						
							| 11 | 
							
								10
							 | 
							oveq2i | 
							⊢ ( ( 𝑃  ∨  𝑄 )  ∧  ( 𝐹  ∨  𝑉 ) )  =  ( ( 𝑃  ∨  𝑄 )  ∧  ( 𝐹  ∨  ( ( 𝑅  ∨  𝑆 )  ∧  𝑊 ) ) )  | 
						
						
							| 12 | 
							
								8 11
							 | 
							eqtr4i | 
							⊢ 𝐺  =  ( ( 𝑃  ∨  𝑄 )  ∧  ( 𝐹  ∨  𝑉 ) )  |