| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mndifsplit.b |  | 
						
							| 2 |  | mndifsplit.0g |  | 
						
							| 3 |  | mndifsplit.pg |  | 
						
							| 4 |  | pm2.21 |  | 
						
							| 5 | 4 | imp |  | 
						
							| 6 | 5 | 3ad2antl3 |  | 
						
							| 7 | 1 3 2 | mndrid |  | 
						
							| 8 | 7 | 3adant3 |  | 
						
							| 9 | 8 | adantr |  | 
						
							| 10 |  | iftrue |  | 
						
							| 11 |  | iffalse |  | 
						
							| 12 | 10 11 | oveqan12d |  | 
						
							| 13 | 12 | adantl |  | 
						
							| 14 |  | iftrue |  | 
						
							| 15 | 14 | orcs |  | 
						
							| 16 | 15 | ad2antrl |  | 
						
							| 17 | 9 13 16 | 3eqtr4rd |  | 
						
							| 18 | 1 3 2 | mndlid |  | 
						
							| 19 | 18 | 3adant3 |  | 
						
							| 20 | 19 | adantr |  | 
						
							| 21 |  | iffalse |  | 
						
							| 22 |  | iftrue |  | 
						
							| 23 | 21 22 | oveqan12d |  | 
						
							| 24 | 23 | adantl |  | 
						
							| 25 | 14 | olcs |  | 
						
							| 26 | 25 | ad2antll |  | 
						
							| 27 | 20 24 26 | 3eqtr4rd |  | 
						
							| 28 |  | simp1 |  | 
						
							| 29 | 1 2 | mndidcl |  | 
						
							| 30 | 1 3 2 | mndlid |  | 
						
							| 31 | 28 29 30 | syl2anc2 |  | 
						
							| 32 | 31 | adantr |  | 
						
							| 33 | 21 11 | oveqan12d |  | 
						
							| 34 | 33 | adantl |  | 
						
							| 35 |  | ioran |  | 
						
							| 36 |  | iffalse |  | 
						
							| 37 | 35 36 | sylbir |  | 
						
							| 38 | 37 | adantl |  | 
						
							| 39 | 32 34 38 | 3eqtr4rd |  | 
						
							| 40 | 6 17 27 39 | 4casesdan |  |