| Step | Hyp | Ref | Expression | 
						
							| 1 |  | cnfldbas |  |-  CC = ( Base ` CCfld ) | 
						
							| 2 | 1 | a1i |  |-  ( T. -> CC = ( Base ` CCfld ) ) | 
						
							| 3 |  | cnfldadd |  |-  + = ( +g ` CCfld ) | 
						
							| 4 | 3 | a1i |  |-  ( T. -> + = ( +g ` CCfld ) ) | 
						
							| 5 |  | cnfldmul |  |-  x. = ( .r ` CCfld ) | 
						
							| 6 | 5 | a1i |  |-  ( T. -> x. = ( .r ` CCfld ) ) | 
						
							| 7 |  | addcl |  |-  ( ( x e. CC /\ y e. CC ) -> ( x + y ) e. CC ) | 
						
							| 8 |  | addass |  |-  ( ( x e. CC /\ y e. CC /\ z e. CC ) -> ( ( x + y ) + z ) = ( x + ( y + z ) ) ) | 
						
							| 9 |  | 0cn |  |-  0 e. CC | 
						
							| 10 |  | addlid |  |-  ( x e. CC -> ( 0 + x ) = x ) | 
						
							| 11 |  | negcl |  |-  ( x e. CC -> -u x e. CC ) | 
						
							| 12 |  | addcom |  |-  ( ( -u x e. CC /\ x e. CC ) -> ( -u x + x ) = ( x + -u x ) ) | 
						
							| 13 | 11 12 | mpancom |  |-  ( x e. CC -> ( -u x + x ) = ( x + -u x ) ) | 
						
							| 14 |  | negid |  |-  ( x e. CC -> ( x + -u x ) = 0 ) | 
						
							| 15 | 13 14 | eqtrd |  |-  ( x e. CC -> ( -u x + x ) = 0 ) | 
						
							| 16 | 1 3 7 8 9 10 11 15 | isgrpi |  |-  CCfld e. Grp | 
						
							| 17 | 16 | a1i |  |-  ( T. -> CCfld e. Grp ) | 
						
							| 18 |  | mulcl |  |-  ( ( x e. CC /\ y e. CC ) -> ( x x. y ) e. CC ) | 
						
							| 19 | 18 | 3adant1 |  |-  ( ( T. /\ x e. CC /\ y e. CC ) -> ( x x. y ) e. CC ) | 
						
							| 20 |  | mulass |  |-  ( ( x e. CC /\ y e. CC /\ z e. CC ) -> ( ( x x. y ) x. z ) = ( x x. ( y x. z ) ) ) | 
						
							| 21 | 20 | adantl |  |-  ( ( T. /\ ( x e. CC /\ y e. CC /\ z e. CC ) ) -> ( ( x x. y ) x. z ) = ( x x. ( y x. z ) ) ) | 
						
							| 22 |  | adddi |  |-  ( ( x e. CC /\ y e. CC /\ z e. CC ) -> ( x x. ( y + z ) ) = ( ( x x. y ) + ( x x. z ) ) ) | 
						
							| 23 | 22 | adantl |  |-  ( ( T. /\ ( x e. CC /\ y e. CC /\ z e. CC ) ) -> ( x x. ( y + z ) ) = ( ( x x. y ) + ( x x. z ) ) ) | 
						
							| 24 |  | adddir |  |-  ( ( x e. CC /\ y e. CC /\ z e. CC ) -> ( ( x + y ) x. z ) = ( ( x x. z ) + ( y x. z ) ) ) | 
						
							| 25 | 24 | adantl |  |-  ( ( T. /\ ( x e. CC /\ y e. CC /\ z e. CC ) ) -> ( ( x + y ) x. z ) = ( ( x x. z ) + ( y x. z ) ) ) | 
						
							| 26 |  | 1cnd |  |-  ( T. -> 1 e. CC ) | 
						
							| 27 |  | mullid |  |-  ( x e. CC -> ( 1 x. x ) = x ) | 
						
							| 28 | 27 | adantl |  |-  ( ( T. /\ x e. CC ) -> ( 1 x. x ) = x ) | 
						
							| 29 |  | mulrid |  |-  ( x e. CC -> ( x x. 1 ) = x ) | 
						
							| 30 | 29 | adantl |  |-  ( ( T. /\ x e. CC ) -> ( x x. 1 ) = x ) | 
						
							| 31 |  | mulcom |  |-  ( ( x e. CC /\ y e. CC ) -> ( x x. y ) = ( y x. x ) ) | 
						
							| 32 | 31 | 3adant1 |  |-  ( ( T. /\ x e. CC /\ y e. CC ) -> ( x x. y ) = ( y x. x ) ) | 
						
							| 33 | 2 4 6 17 19 21 23 25 26 28 30 32 | iscrngd |  |-  ( T. -> CCfld e. CRing ) | 
						
							| 34 | 33 | mptru |  |-  CCfld e. CRing |