| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mddmdin0.1 |  |-  A e. CH | 
						
							| 2 |  | mddmdin0.2 |  |-  B e. CH | 
						
							| 3 |  | mddmdin0.3 |  |-  A. x e. CH A. y e. CH ( ( x MH* y /\ ( x i^i y ) = 0H ) -> x MH y ) | 
						
							| 4 |  | inindir |  |-  ( ( A i^i B ) i^i ( _|_ ` ( A i^i B ) ) ) = ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i ( B i^i ( _|_ ` ( A i^i B ) ) ) ) | 
						
							| 5 | 1 2 | chincli |  |-  ( A i^i B ) e. CH | 
						
							| 6 | 5 | chocini |  |-  ( ( A i^i B ) i^i ( _|_ ` ( A i^i B ) ) ) = 0H | 
						
							| 7 | 4 6 | eqtr3i |  |-  ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i ( B i^i ( _|_ ` ( A i^i B ) ) ) ) = 0H | 
						
							| 8 | 5 | choccli |  |-  ( _|_ ` ( A i^i B ) ) e. CH | 
						
							| 9 | 1 8 | chincli |  |-  ( A i^i ( _|_ ` ( A i^i B ) ) ) e. CH | 
						
							| 10 | 2 8 | chincli |  |-  ( B i^i ( _|_ ` ( A i^i B ) ) ) e. CH | 
						
							| 11 |  | breq1 |  |-  ( x = ( A i^i ( _|_ ` ( A i^i B ) ) ) -> ( x MH* y <-> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* y ) ) | 
						
							| 12 |  | ineq1 |  |-  ( x = ( A i^i ( _|_ ` ( A i^i B ) ) ) -> ( x i^i y ) = ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i y ) ) | 
						
							| 13 | 12 | eqeq1d |  |-  ( x = ( A i^i ( _|_ ` ( A i^i B ) ) ) -> ( ( x i^i y ) = 0H <-> ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i y ) = 0H ) ) | 
						
							| 14 | 11 13 | anbi12d |  |-  ( x = ( A i^i ( _|_ ` ( A i^i B ) ) ) -> ( ( x MH* y /\ ( x i^i y ) = 0H ) <-> ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* y /\ ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i y ) = 0H ) ) ) | 
						
							| 15 |  | breq1 |  |-  ( x = ( A i^i ( _|_ ` ( A i^i B ) ) ) -> ( x MH y <-> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH y ) ) | 
						
							| 16 | 14 15 | imbi12d |  |-  ( x = ( A i^i ( _|_ ` ( A i^i B ) ) ) -> ( ( ( x MH* y /\ ( x i^i y ) = 0H ) -> x MH y ) <-> ( ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* y /\ ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i y ) = 0H ) -> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH y ) ) ) | 
						
							| 17 |  | breq2 |  |-  ( y = ( B i^i ( _|_ ` ( A i^i B ) ) ) -> ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* y <-> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* ( B i^i ( _|_ ` ( A i^i B ) ) ) ) ) | 
						
							| 18 |  | ineq2 |  |-  ( y = ( B i^i ( _|_ ` ( A i^i B ) ) ) -> ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i y ) = ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i ( B i^i ( _|_ ` ( A i^i B ) ) ) ) ) | 
						
							| 19 | 18 | eqeq1d |  |-  ( y = ( B i^i ( _|_ ` ( A i^i B ) ) ) -> ( ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i y ) = 0H <-> ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i ( B i^i ( _|_ ` ( A i^i B ) ) ) ) = 0H ) ) | 
						
							| 20 | 17 19 | anbi12d |  |-  ( y = ( B i^i ( _|_ ` ( A i^i B ) ) ) -> ( ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* y /\ ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i y ) = 0H ) <-> ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* ( B i^i ( _|_ ` ( A i^i B ) ) ) /\ ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i ( B i^i ( _|_ ` ( A i^i B ) ) ) ) = 0H ) ) ) | 
						
							| 21 |  | breq2 |  |-  ( y = ( B i^i ( _|_ ` ( A i^i B ) ) ) -> ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH y <-> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH ( B i^i ( _|_ ` ( A i^i B ) ) ) ) ) | 
						
							| 22 | 20 21 | imbi12d |  |-  ( y = ( B i^i ( _|_ ` ( A i^i B ) ) ) -> ( ( ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* y /\ ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i y ) = 0H ) -> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH y ) <-> ( ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* ( B i^i ( _|_ ` ( A i^i B ) ) ) /\ ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i ( B i^i ( _|_ ` ( A i^i B ) ) ) ) = 0H ) -> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH ( B i^i ( _|_ ` ( A i^i B ) ) ) ) ) ) | 
						
							| 23 | 16 22 | rspc2v |  |-  ( ( ( A i^i ( _|_ ` ( A i^i B ) ) ) e. CH /\ ( B i^i ( _|_ ` ( A i^i B ) ) ) e. CH ) -> ( A. x e. CH A. y e. CH ( ( x MH* y /\ ( x i^i y ) = 0H ) -> x MH y ) -> ( ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* ( B i^i ( _|_ ` ( A i^i B ) ) ) /\ ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i ( B i^i ( _|_ ` ( A i^i B ) ) ) ) = 0H ) -> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH ( B i^i ( _|_ ` ( A i^i B ) ) ) ) ) ) | 
						
							| 24 | 9 10 23 | mp2an |  |-  ( A. x e. CH A. y e. CH ( ( x MH* y /\ ( x i^i y ) = 0H ) -> x MH y ) -> ( ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* ( B i^i ( _|_ ` ( A i^i B ) ) ) /\ ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i ( B i^i ( _|_ ` ( A i^i B ) ) ) ) = 0H ) -> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH ( B i^i ( _|_ ` ( A i^i B ) ) ) ) ) | 
						
							| 25 | 3 24 | ax-mp |  |-  ( ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* ( B i^i ( _|_ ` ( A i^i B ) ) ) /\ ( ( A i^i ( _|_ ` ( A i^i B ) ) ) i^i ( B i^i ( _|_ ` ( A i^i B ) ) ) ) = 0H ) -> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH ( B i^i ( _|_ ` ( A i^i B ) ) ) ) | 
						
							| 26 | 7 25 | mpan2 |  |-  ( ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* ( B i^i ( _|_ ` ( A i^i B ) ) ) -> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH ( B i^i ( _|_ ` ( A i^i B ) ) ) ) | 
						
							| 27 | 1 2 | dmdcompli |  |-  ( A MH* B <-> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH* ( B i^i ( _|_ ` ( A i^i B ) ) ) ) | 
						
							| 28 | 1 2 | mdcompli |  |-  ( A MH B <-> ( A i^i ( _|_ ` ( A i^i B ) ) ) MH ( B i^i ( _|_ ` ( A i^i B ) ) ) ) | 
						
							| 29 | 26 27 28 | 3imtr4i |  |-  ( A MH* B -> A MH B ) |