| Step | Hyp | Ref | Expression | 
						
							| 0 |  | crngcALTV |  |-  RngCatALTV | 
						
							| 1 |  | vu |  |-  u | 
						
							| 2 |  | cvv |  |-  _V | 
						
							| 3 | 1 | cv |  |-  u | 
						
							| 4 |  | crng |  |-  Rng | 
						
							| 5 | 3 4 | cin |  |-  ( u i^i Rng ) | 
						
							| 6 |  | vb |  |-  b | 
						
							| 7 |  | cbs |  |-  Base | 
						
							| 8 |  | cnx |  |-  ndx | 
						
							| 9 | 8 7 | cfv |  |-  ( Base ` ndx ) | 
						
							| 10 | 6 | cv |  |-  b | 
						
							| 11 | 9 10 | cop |  |-  <. ( Base ` ndx ) , b >. | 
						
							| 12 |  | chom |  |-  Hom | 
						
							| 13 | 8 12 | cfv |  |-  ( Hom ` ndx ) | 
						
							| 14 |  | vx |  |-  x | 
						
							| 15 |  | vy |  |-  y | 
						
							| 16 | 14 | cv |  |-  x | 
						
							| 17 |  | crnghm |  |-  RngHom | 
						
							| 18 | 15 | cv |  |-  y | 
						
							| 19 | 16 18 17 | co |  |-  ( x RngHom y ) | 
						
							| 20 | 14 15 10 10 19 | cmpo |  |-  ( x e. b , y e. b |-> ( x RngHom y ) ) | 
						
							| 21 | 13 20 | cop |  |-  <. ( Hom ` ndx ) , ( x e. b , y e. b |-> ( x RngHom y ) ) >. | 
						
							| 22 |  | cco |  |-  comp | 
						
							| 23 | 8 22 | cfv |  |-  ( comp ` ndx ) | 
						
							| 24 |  | vv |  |-  v | 
						
							| 25 | 10 10 | cxp |  |-  ( b X. b ) | 
						
							| 26 |  | vz |  |-  z | 
						
							| 27 |  | vg |  |-  g | 
						
							| 28 |  | c2nd |  |-  2nd | 
						
							| 29 | 24 | cv |  |-  v | 
						
							| 30 | 29 28 | cfv |  |-  ( 2nd ` v ) | 
						
							| 31 | 26 | cv |  |-  z | 
						
							| 32 | 30 31 17 | co |  |-  ( ( 2nd ` v ) RngHom z ) | 
						
							| 33 |  | vf |  |-  f | 
						
							| 34 |  | c1st |  |-  1st | 
						
							| 35 | 29 34 | cfv |  |-  ( 1st ` v ) | 
						
							| 36 | 35 30 17 | co |  |-  ( ( 1st ` v ) RngHom ( 2nd ` v ) ) | 
						
							| 37 | 27 | cv |  |-  g | 
						
							| 38 | 33 | cv |  |-  f | 
						
							| 39 | 37 38 | ccom |  |-  ( g o. f ) | 
						
							| 40 | 27 33 32 36 39 | cmpo |  |-  ( g e. ( ( 2nd ` v ) RngHom z ) , f e. ( ( 1st ` v ) RngHom ( 2nd ` v ) ) |-> ( g o. f ) ) | 
						
							| 41 | 24 26 25 10 40 | cmpo |  |-  ( v e. ( b X. b ) , z e. b |-> ( g e. ( ( 2nd ` v ) RngHom z ) , f e. ( ( 1st ` v ) RngHom ( 2nd ` v ) ) |-> ( g o. f ) ) ) | 
						
							| 42 | 23 41 | cop |  |-  <. ( comp ` ndx ) , ( v e. ( b X. b ) , z e. b |-> ( g e. ( ( 2nd ` v ) RngHom z ) , f e. ( ( 1st ` v ) RngHom ( 2nd ` v ) ) |-> ( g o. f ) ) ) >. | 
						
							| 43 | 11 21 42 | ctp |  |-  { <. ( Base ` ndx ) , b >. , <. ( Hom ` ndx ) , ( x e. b , y e. b |-> ( x RngHom y ) ) >. , <. ( comp ` ndx ) , ( v e. ( b X. b ) , z e. b |-> ( g e. ( ( 2nd ` v ) RngHom z ) , f e. ( ( 1st ` v ) RngHom ( 2nd ` v ) ) |-> ( g o. f ) ) ) >. } | 
						
							| 44 | 6 5 43 | csb |  |-  [_ ( u i^i Rng ) / b ]_ { <. ( Base ` ndx ) , b >. , <. ( Hom ` ndx ) , ( x e. b , y e. b |-> ( x RngHom y ) ) >. , <. ( comp ` ndx ) , ( v e. ( b X. b ) , z e. b |-> ( g e. ( ( 2nd ` v ) RngHom z ) , f e. ( ( 1st ` v ) RngHom ( 2nd ` v ) ) |-> ( g o. f ) ) ) >. } | 
						
							| 45 | 1 2 44 | cmpt |  |-  ( u e. _V |-> [_ ( u i^i Rng ) / b ]_ { <. ( Base ` ndx ) , b >. , <. ( Hom ` ndx ) , ( x e. b , y e. b |-> ( x RngHom y ) ) >. , <. ( comp ` ndx ) , ( v e. ( b X. b ) , z e. b |-> ( g e. ( ( 2nd ` v ) RngHom z ) , f e. ( ( 1st ` v ) RngHom ( 2nd ` v ) ) |-> ( g o. f ) ) ) >. } ) | 
						
							| 46 | 0 45 | wceq |  |-  RngCatALTV = ( u e. _V |-> [_ ( u i^i Rng ) / b ]_ { <. ( Base ` ndx ) , b >. , <. ( Hom ` ndx ) , ( x e. b , y e. b |-> ( x RngHom y ) ) >. , <. ( comp ` ndx ) , ( v e. ( b X. b ) , z e. b |-> ( g e. ( ( 2nd ` v ) RngHom z ) , f e. ( ( 1st ` v ) RngHom ( 2nd ` v ) ) |-> ( g o. f ) ) ) >. } ) |