| Step | Hyp | Ref | Expression | 
						
							| 1 |  | issubmndb.b |  |-  B = ( Base ` G ) | 
						
							| 2 |  | issubmndb.z |  |-  .0. = ( 0g ` G ) | 
						
							| 3 |  | eqid |  |-  ( G |`s S ) = ( G |`s S ) | 
						
							| 4 | 1 2 3 | issubm2 |  |-  ( G e. Mnd -> ( S e. ( SubMnd ` G ) <-> ( S C_ B /\ .0. e. S /\ ( G |`s S ) e. Mnd ) ) ) | 
						
							| 5 |  | 3anrot |  |-  ( ( ( G |`s S ) e. Mnd /\ S C_ B /\ .0. e. S ) <-> ( S C_ B /\ .0. e. S /\ ( G |`s S ) e. Mnd ) ) | 
						
							| 6 |  | 3anass |  |-  ( ( ( G |`s S ) e. Mnd /\ S C_ B /\ .0. e. S ) <-> ( ( G |`s S ) e. Mnd /\ ( S C_ B /\ .0. e. S ) ) ) | 
						
							| 7 | 5 6 | bitr3i |  |-  ( ( S C_ B /\ .0. e. S /\ ( G |`s S ) e. Mnd ) <-> ( ( G |`s S ) e. Mnd /\ ( S C_ B /\ .0. e. S ) ) ) | 
						
							| 8 | 4 7 | bitrdi |  |-  ( G e. Mnd -> ( S e. ( SubMnd ` G ) <-> ( ( G |`s S ) e. Mnd /\ ( S C_ B /\ .0. e. S ) ) ) ) | 
						
							| 9 | 8 | pm5.32i |  |-  ( ( G e. Mnd /\ S e. ( SubMnd ` G ) ) <-> ( G e. Mnd /\ ( ( G |`s S ) e. Mnd /\ ( S C_ B /\ .0. e. S ) ) ) ) | 
						
							| 10 |  | submrcl |  |-  ( S e. ( SubMnd ` G ) -> G e. Mnd ) | 
						
							| 11 | 10 | pm4.71ri |  |-  ( S e. ( SubMnd ` G ) <-> ( G e. Mnd /\ S e. ( SubMnd ` G ) ) ) | 
						
							| 12 |  | anass |  |-  ( ( ( G e. Mnd /\ ( G |`s S ) e. Mnd ) /\ ( S C_ B /\ .0. e. S ) ) <-> ( G e. Mnd /\ ( ( G |`s S ) e. Mnd /\ ( S C_ B /\ .0. e. S ) ) ) ) | 
						
							| 13 | 9 11 12 | 3bitr4i |  |-  ( S e. ( SubMnd ` G ) <-> ( ( G e. Mnd /\ ( G |`s S ) e. Mnd ) /\ ( S C_ B /\ .0. e. S ) ) ) |