| Step | Hyp | Ref | Expression | 
						
							| 1 |  | fh1.1 | ⊢ 𝐴  ∈   Cℋ | 
						
							| 2 |  | fh1.2 | ⊢ 𝐵  ∈   Cℋ | 
						
							| 3 |  | fh1.3 | ⊢ 𝐶  ∈   Cℋ | 
						
							| 4 |  | fh1.4 | ⊢ 𝐴  𝐶ℋ  𝐵 | 
						
							| 5 |  | fh1.5 | ⊢ 𝐴  𝐶ℋ  𝐶 | 
						
							| 6 | 1 | choccli | ⊢ ( ⊥ ‘ 𝐴 )  ∈   Cℋ | 
						
							| 7 | 2 | choccli | ⊢ ( ⊥ ‘ 𝐵 )  ∈   Cℋ | 
						
							| 8 | 3 | choccli | ⊢ ( ⊥ ‘ 𝐶 )  ∈   Cℋ | 
						
							| 9 | 1 2 4 | cmcm3ii | ⊢ ( ⊥ ‘ 𝐴 )  𝐶ℋ  𝐵 | 
						
							| 10 | 6 2 9 | cmcm2ii | ⊢ ( ⊥ ‘ 𝐴 )  𝐶ℋ  ( ⊥ ‘ 𝐵 ) | 
						
							| 11 | 1 3 5 | cmcm3ii | ⊢ ( ⊥ ‘ 𝐴 )  𝐶ℋ  𝐶 | 
						
							| 12 | 6 3 11 | cmcm2ii | ⊢ ( ⊥ ‘ 𝐴 )  𝐶ℋ  ( ⊥ ‘ 𝐶 ) | 
						
							| 13 | 6 7 8 10 12 | fh2i | ⊢ ( ( ⊥ ‘ 𝐵 )  ∩  ( ( ⊥ ‘ 𝐴 )  ∨ℋ  ( ⊥ ‘ 𝐶 ) ) )  =  ( ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐴 ) )  ∨ℋ  ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐶 ) ) ) | 
						
							| 14 | 1 3 | chdmm1i | ⊢ ( ⊥ ‘ ( 𝐴  ∩  𝐶 ) )  =  ( ( ⊥ ‘ 𝐴 )  ∨ℋ  ( ⊥ ‘ 𝐶 ) ) | 
						
							| 15 | 14 | ineq2i | ⊢ ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ ( 𝐴  ∩  𝐶 ) ) )  =  ( ( ⊥ ‘ 𝐵 )  ∩  ( ( ⊥ ‘ 𝐴 )  ∨ℋ  ( ⊥ ‘ 𝐶 ) ) ) | 
						
							| 16 | 2 1 | chdmj1i | ⊢ ( ⊥ ‘ ( 𝐵  ∨ℋ  𝐴 ) )  =  ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐴 ) ) | 
						
							| 17 | 2 3 | chdmj1i | ⊢ ( ⊥ ‘ ( 𝐵  ∨ℋ  𝐶 ) )  =  ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐶 ) ) | 
						
							| 18 | 16 17 | oveq12i | ⊢ ( ( ⊥ ‘ ( 𝐵  ∨ℋ  𝐴 ) )  ∨ℋ  ( ⊥ ‘ ( 𝐵  ∨ℋ  𝐶 ) ) )  =  ( ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐴 ) )  ∨ℋ  ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐶 ) ) ) | 
						
							| 19 | 13 15 18 | 3eqtr4ri | ⊢ ( ( ⊥ ‘ ( 𝐵  ∨ℋ  𝐴 ) )  ∨ℋ  ( ⊥ ‘ ( 𝐵  ∨ℋ  𝐶 ) ) )  =  ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ ( 𝐴  ∩  𝐶 ) ) ) | 
						
							| 20 | 2 1 | chjcli | ⊢ ( 𝐵  ∨ℋ  𝐴 )  ∈   Cℋ | 
						
							| 21 | 2 3 | chjcli | ⊢ ( 𝐵  ∨ℋ  𝐶 )  ∈   Cℋ | 
						
							| 22 | 20 21 | chdmm1i | ⊢ ( ⊥ ‘ ( ( 𝐵  ∨ℋ  𝐴 )  ∩  ( 𝐵  ∨ℋ  𝐶 ) ) )  =  ( ( ⊥ ‘ ( 𝐵  ∨ℋ  𝐴 ) )  ∨ℋ  ( ⊥ ‘ ( 𝐵  ∨ℋ  𝐶 ) ) ) | 
						
							| 23 | 1 3 | chincli | ⊢ ( 𝐴  ∩  𝐶 )  ∈   Cℋ | 
						
							| 24 | 2 23 | chdmj1i | ⊢ ( ⊥ ‘ ( 𝐵  ∨ℋ  ( 𝐴  ∩  𝐶 ) ) )  =  ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ ( 𝐴  ∩  𝐶 ) ) ) | 
						
							| 25 | 19 22 24 | 3eqtr4i | ⊢ ( ⊥ ‘ ( ( 𝐵  ∨ℋ  𝐴 )  ∩  ( 𝐵  ∨ℋ  𝐶 ) ) )  =  ( ⊥ ‘ ( 𝐵  ∨ℋ  ( 𝐴  ∩  𝐶 ) ) ) | 
						
							| 26 | 2 23 | chjcli | ⊢ ( 𝐵  ∨ℋ  ( 𝐴  ∩  𝐶 ) )  ∈   Cℋ | 
						
							| 27 | 20 21 | chincli | ⊢ ( ( 𝐵  ∨ℋ  𝐴 )  ∩  ( 𝐵  ∨ℋ  𝐶 ) )  ∈   Cℋ | 
						
							| 28 | 26 27 | chcon3i | ⊢ ( ( 𝐵  ∨ℋ  ( 𝐴  ∩  𝐶 ) )  =  ( ( 𝐵  ∨ℋ  𝐴 )  ∩  ( 𝐵  ∨ℋ  𝐶 ) )  ↔  ( ⊥ ‘ ( ( 𝐵  ∨ℋ  𝐴 )  ∩  ( 𝐵  ∨ℋ  𝐶 ) ) )  =  ( ⊥ ‘ ( 𝐵  ∨ℋ  ( 𝐴  ∩  𝐶 ) ) ) ) | 
						
							| 29 | 25 28 | mpbir | ⊢ ( 𝐵  ∨ℋ  ( 𝐴  ∩  𝐶 ) )  =  ( ( 𝐵  ∨ℋ  𝐴 )  ∩  ( 𝐵  ∨ℋ  𝐶 ) ) |