| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							pjoml2.1 | 
							 |-  A e. CH  | 
						
						
							| 2 | 
							
								
							 | 
							pjoml2.2 | 
							 |-  B e. CH  | 
						
						
							| 3 | 
							
								1
							 | 
							choccli | 
							 |-  ( _|_ ` A ) e. CH  | 
						
						
							| 4 | 
							
								3 2
							 | 
							chincli | 
							 |-  ( ( _|_ ` A ) i^i B ) e. CH  | 
						
						
							| 5 | 
							
								1 2
							 | 
							pjoml2i | 
							 |-  ( A C_ B -> ( A vH ( ( _|_ ` A ) i^i B ) ) = B )  | 
						
						
							| 6 | 
							
								2
							 | 
							choccli | 
							 |-  ( _|_ ` B ) e. CH  | 
						
						
							| 7 | 
							
								1 6
							 | 
							chub1i | 
							 |-  A C_ ( A vH ( _|_ ` B ) )  | 
						
						
							| 8 | 
							
								1 2
							 | 
							chdmm2i | 
							 |-  ( _|_ ` ( ( _|_ ` A ) i^i B ) ) = ( A vH ( _|_ ` B ) )  | 
						
						
							| 9 | 
							
								7 8
							 | 
							sseqtrri | 
							 |-  A C_ ( _|_ ` ( ( _|_ ` A ) i^i B ) )  | 
						
						
							| 10 | 
							
								5 9
							 | 
							jctil | 
							 |-  ( A C_ B -> ( A C_ ( _|_ ` ( ( _|_ ` A ) i^i B ) ) /\ ( A vH ( ( _|_ ` A ) i^i B ) ) = B ) )  | 
						
						
							| 11 | 
							
								
							 | 
							fveq2 | 
							 |-  ( x = ( ( _|_ ` A ) i^i B ) -> ( _|_ ` x ) = ( _|_ ` ( ( _|_ ` A ) i^i B ) ) )  | 
						
						
							| 12 | 
							
								11
							 | 
							sseq2d | 
							 |-  ( x = ( ( _|_ ` A ) i^i B ) -> ( A C_ ( _|_ ` x ) <-> A C_ ( _|_ ` ( ( _|_ ` A ) i^i B ) ) ) )  | 
						
						
							| 13 | 
							
								
							 | 
							oveq2 | 
							 |-  ( x = ( ( _|_ ` A ) i^i B ) -> ( A vH x ) = ( A vH ( ( _|_ ` A ) i^i B ) ) )  | 
						
						
							| 14 | 
							
								13
							 | 
							eqeq1d | 
							 |-  ( x = ( ( _|_ ` A ) i^i B ) -> ( ( A vH x ) = B <-> ( A vH ( ( _|_ ` A ) i^i B ) ) = B ) )  | 
						
						
							| 15 | 
							
								12 14
							 | 
							anbi12d | 
							 |-  ( x = ( ( _|_ ` A ) i^i B ) -> ( ( A C_ ( _|_ ` x ) /\ ( A vH x ) = B ) <-> ( A C_ ( _|_ ` ( ( _|_ ` A ) i^i B ) ) /\ ( A vH ( ( _|_ ` A ) i^i B ) ) = B ) ) )  | 
						
						
							| 16 | 
							
								15
							 | 
							rspcev | 
							 |-  ( ( ( ( _|_ ` A ) i^i B ) e. CH /\ ( A C_ ( _|_ ` ( ( _|_ ` A ) i^i B ) ) /\ ( A vH ( ( _|_ ` A ) i^i B ) ) = B ) ) -> E. x e. CH ( A C_ ( _|_ ` x ) /\ ( A vH x ) = B ) )  | 
						
						
							| 17 | 
							
								4 10 16
							 | 
							sylancr | 
							 |-  ( A C_ B -> E. x e. CH ( A C_ ( _|_ ` x ) /\ ( A vH x ) = B ) )  |