| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							cvrne.b | 
							 |-  B = ( Base ` K )  | 
						
						
							| 2 | 
							
								
							 | 
							cvrne.c | 
							 |-  C = (   | 
						
						
							| 3 | 
							
								
							 | 
							eqid | 
							 |-  X = X  | 
						
						
							| 4 | 
							
								
							 | 
							simpll | 
							 |-  ( ( ( K e. A /\ X e. B ) /\ X C X ) -> K e. A )  | 
						
						
							| 5 | 
							
								
							 | 
							simplr | 
							 |-  ( ( ( K e. A /\ X e. B ) /\ X C X ) -> X e. B )  | 
						
						
							| 6 | 
							
								
							 | 
							simpr | 
							 |-  ( ( ( K e. A /\ X e. B ) /\ X C X ) -> X C X )  | 
						
						
							| 7 | 
							
								1 2
							 | 
							cvrne | 
							 |-  ( ( ( K e. A /\ X e. B /\ X e. B ) /\ X C X ) -> X =/= X )  | 
						
						
							| 8 | 
							
								4 5 5 6 7
							 | 
							syl31anc | 
							 |-  ( ( ( K e. A /\ X e. B ) /\ X C X ) -> X =/= X )  | 
						
						
							| 9 | 
							
								8
							 | 
							ex | 
							 |-  ( ( K e. A /\ X e. B ) -> ( X C X -> X =/= X ) )  | 
						
						
							| 10 | 
							
								9
							 | 
							necon2bd | 
							 |-  ( ( K e. A /\ X e. B ) -> ( X = X -> -. X C X ) )  | 
						
						
							| 11 | 
							
								3 10
							 | 
							mpi | 
							 |-  ( ( K e. A /\ X e. B ) -> -. X C X )  |