| Step | Hyp | Ref | Expression | 
						
							| 1 |  | brpprod.1 |  | 
						
							| 2 |  | brpprod.2 |  | 
						
							| 3 |  | brpprod.3 |  | 
						
							| 4 |  | brpprod.4 |  | 
						
							| 5 |  | df-pprod |  | 
						
							| 6 | 5 | breqi |  | 
						
							| 7 |  | opex |  | 
						
							| 8 | 7 3 4 | brtxp |  | 
						
							| 9 | 7 3 | brco |  | 
						
							| 10 | 1 2 | opelvv |  | 
						
							| 11 |  | vex |  | 
						
							| 12 | 11 | brresi |  | 
						
							| 13 | 10 12 | mpbiran |  | 
						
							| 14 | 1 2 | br1steq |  | 
						
							| 15 | 13 14 | bitri |  | 
						
							| 16 | 15 | anbi1i |  | 
						
							| 17 | 16 | exbii |  | 
						
							| 18 |  | breq1 |  | 
						
							| 19 | 1 18 | ceqsexv |  | 
						
							| 20 | 9 17 19 | 3bitri |  | 
						
							| 21 | 7 4 | brco |  | 
						
							| 22 |  | vex |  | 
						
							| 23 | 22 | brresi |  | 
						
							| 24 | 10 23 | mpbiran |  | 
						
							| 25 | 1 2 | br2ndeq |  | 
						
							| 26 | 24 25 | bitri |  | 
						
							| 27 | 26 | anbi1i |  | 
						
							| 28 | 27 | exbii |  | 
						
							| 29 |  | breq1 |  | 
						
							| 30 | 2 29 | ceqsexv |  | 
						
							| 31 | 21 28 30 | 3bitri |  | 
						
							| 32 | 20 31 | anbi12i |  | 
						
							| 33 | 6 8 32 | 3bitri |  |