| Step | Hyp | Ref | Expression | 
						
							| 1 |  | xpord2.1 |  | 
						
							| 2 |  | opex |  | 
						
							| 3 |  | opex |  | 
						
							| 4 |  | eleq1 |  | 
						
							| 5 |  | opelxp |  | 
						
							| 6 | 4 5 | bitrdi |  | 
						
							| 7 |  | vex |  | 
						
							| 8 |  | vex |  | 
						
							| 9 | 7 8 | op1std |  | 
						
							| 10 | 9 | breq1d |  | 
						
							| 11 | 9 | eqeq1d |  | 
						
							| 12 | 10 11 | orbi12d |  | 
						
							| 13 | 7 8 | op2ndd |  | 
						
							| 14 | 13 | breq1d |  | 
						
							| 15 | 13 | eqeq1d |  | 
						
							| 16 | 14 15 | orbi12d |  | 
						
							| 17 |  | neeq1 |  | 
						
							| 18 | 12 16 17 | 3anbi123d |  | 
						
							| 19 | 6 18 | 3anbi13d |  | 
						
							| 20 |  | eleq1 |  | 
						
							| 21 |  | opelxp |  | 
						
							| 22 | 20 21 | bitrdi |  | 
						
							| 23 |  | vex |  | 
						
							| 24 |  | vex |  | 
						
							| 25 | 23 24 | op1std |  | 
						
							| 26 | 25 | breq2d |  | 
						
							| 27 | 25 | eqeq2d |  | 
						
							| 28 | 26 27 | orbi12d |  | 
						
							| 29 | 23 24 | op2ndd |  | 
						
							| 30 | 29 | breq2d |  | 
						
							| 31 | 29 | eqeq2d |  | 
						
							| 32 | 30 31 | orbi12d |  | 
						
							| 33 |  | neeq2 |  | 
						
							| 34 | 7 8 | opthne |  | 
						
							| 35 | 33 34 | bitrdi |  | 
						
							| 36 | 28 32 35 | 3anbi123d |  | 
						
							| 37 | 22 36 | 3anbi23d |  | 
						
							| 38 | 2 3 19 37 1 | brab |  |