| Step | Hyp | Ref | Expression | 
						
							| 1 |  | sspba.x |  |-  X = ( BaseSet ` U ) | 
						
							| 2 |  | sspba.y |  |-  Y = ( BaseSet ` W ) | 
						
							| 3 |  | sspba.h |  |-  H = ( SubSp ` U ) | 
						
							| 4 |  | eqid |  |-  ( +v ` U ) = ( +v ` U ) | 
						
							| 5 |  | eqid |  |-  ( +v ` W ) = ( +v ` W ) | 
						
							| 6 |  | eqid |  |-  ( .sOLD ` U ) = ( .sOLD ` U ) | 
						
							| 7 |  | eqid |  |-  ( .sOLD ` W ) = ( .sOLD ` W ) | 
						
							| 8 |  | eqid |  |-  ( normCV ` U ) = ( normCV ` U ) | 
						
							| 9 |  | eqid |  |-  ( normCV ` W ) = ( normCV ` W ) | 
						
							| 10 | 4 5 6 7 8 9 3 | isssp |  |-  ( U e. NrmCVec -> ( W e. H <-> ( W e. NrmCVec /\ ( ( +v ` W ) C_ ( +v ` U ) /\ ( .sOLD ` W ) C_ ( .sOLD ` U ) /\ ( normCV ` W ) C_ ( normCV ` U ) ) ) ) ) | 
						
							| 11 | 10 | simplbda |  |-  ( ( U e. NrmCVec /\ W e. H ) -> ( ( +v ` W ) C_ ( +v ` U ) /\ ( .sOLD ` W ) C_ ( .sOLD ` U ) /\ ( normCV ` W ) C_ ( normCV ` U ) ) ) | 
						
							| 12 | 11 | simp1d |  |-  ( ( U e. NrmCVec /\ W e. H ) -> ( +v ` W ) C_ ( +v ` U ) ) | 
						
							| 13 |  | rnss |  |-  ( ( +v ` W ) C_ ( +v ` U ) -> ran ( +v ` W ) C_ ran ( +v ` U ) ) | 
						
							| 14 | 12 13 | syl |  |-  ( ( U e. NrmCVec /\ W e. H ) -> ran ( +v ` W ) C_ ran ( +v ` U ) ) | 
						
							| 15 | 2 5 | bafval |  |-  Y = ran ( +v ` W ) | 
						
							| 16 | 1 4 | bafval |  |-  X = ran ( +v ` U ) | 
						
							| 17 | 14 15 16 | 3sstr4g |  |-  ( ( U e. NrmCVec /\ W e. H ) -> Y C_ X ) |