| Step | Hyp | Ref | Expression | 
						
							| 0 |  | cperpg |  |-  perpG | 
						
							| 1 |  | vg |  |-  g | 
						
							| 2 |  | cvv |  |-  _V | 
						
							| 3 |  | va |  |-  a | 
						
							| 4 |  | vb |  |-  b | 
						
							| 5 | 3 | cv |  |-  a | 
						
							| 6 |  | clng |  |-  LineG | 
						
							| 7 | 1 | cv |  |-  g | 
						
							| 8 | 7 6 | cfv |  |-  ( LineG ` g ) | 
						
							| 9 | 8 | crn |  |-  ran ( LineG ` g ) | 
						
							| 10 | 5 9 | wcel |  |-  a e. ran ( LineG ` g ) | 
						
							| 11 | 4 | cv |  |-  b | 
						
							| 12 | 11 9 | wcel |  |-  b e. ran ( LineG ` g ) | 
						
							| 13 | 10 12 | wa |  |-  ( a e. ran ( LineG ` g ) /\ b e. ran ( LineG ` g ) ) | 
						
							| 14 |  | vx |  |-  x | 
						
							| 15 | 5 11 | cin |  |-  ( a i^i b ) | 
						
							| 16 |  | vu |  |-  u | 
						
							| 17 |  | vv |  |-  v | 
						
							| 18 | 16 | cv |  |-  u | 
						
							| 19 | 14 | cv |  |-  x | 
						
							| 20 | 17 | cv |  |-  v | 
						
							| 21 | 18 19 20 | cs3 |  |-  <" u x v "> | 
						
							| 22 |  | crag |  |-  raG | 
						
							| 23 | 7 22 | cfv |  |-  ( raG ` g ) | 
						
							| 24 | 21 23 | wcel |  |-  <" u x v "> e. ( raG ` g ) | 
						
							| 25 | 24 17 11 | wral |  |-  A. v e. b <" u x v "> e. ( raG ` g ) | 
						
							| 26 | 25 16 5 | wral |  |-  A. u e. a A. v e. b <" u x v "> e. ( raG ` g ) | 
						
							| 27 | 26 14 15 | wrex |  |-  E. x e. ( a i^i b ) A. u e. a A. v e. b <" u x v "> e. ( raG ` g ) | 
						
							| 28 | 13 27 | wa |  |-  ( ( a e. ran ( LineG ` g ) /\ b e. ran ( LineG ` g ) ) /\ E. x e. ( a i^i b ) A. u e. a A. v e. b <" u x v "> e. ( raG ` g ) ) | 
						
							| 29 | 28 3 4 | copab |  |-  { <. a , b >. | ( ( a e. ran ( LineG ` g ) /\ b e. ran ( LineG ` g ) ) /\ E. x e. ( a i^i b ) A. u e. a A. v e. b <" u x v "> e. ( raG ` g ) ) } | 
						
							| 30 | 1 2 29 | cmpt |  |-  ( g e. _V |-> { <. a , b >. | ( ( a e. ran ( LineG ` g ) /\ b e. ran ( LineG ` g ) ) /\ E. x e. ( a i^i b ) A. u e. a A. v e. b <" u x v "> e. ( raG ` g ) ) } ) | 
						
							| 31 | 0 30 | wceq |  |-  perpG = ( g e. _V |-> { <. a , b >. | ( ( a e. ran ( LineG ` g ) /\ b e. ran ( LineG ` g ) ) /\ E. x e. ( a i^i b ) A. u e. a A. v e. b <" u x v "> e. ( raG ` g ) ) } ) |