| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mdetfval1.d |  | 
						
							| 2 |  | mdetfval1.a |  | 
						
							| 3 |  | mdetfval1.b |  | 
						
							| 4 |  | mdetfval1.p |  | 
						
							| 5 |  | mdetfval1.y |  | 
						
							| 6 |  | mdetfval1.s |  | 
						
							| 7 |  | mdetfval1.t |  | 
						
							| 8 |  | mdetfval1.u |  | 
						
							| 9 | 1 2 3 4 5 6 7 8 | mdetfval |  | 
						
							| 10 | 4 6 | cofipsgn |  | 
						
							| 11 | 10 | oveq1d |  | 
						
							| 12 | 11 | mpteq2dva |  | 
						
							| 13 | 12 | oveq2d |  | 
						
							| 14 | 13 | mpteq2dv |  | 
						
							| 15 | 9 14 | eqtrid |  | 
						
							| 16 |  | df-nel |  | 
						
							| 17 | 1 | nfimdetndef |  | 
						
							| 18 | 2 | fveq2i |  | 
						
							| 19 | 3 18 | eqtri |  | 
						
							| 20 | 16 | biimpi |  | 
						
							| 21 | 20 | intnanrd |  | 
						
							| 22 |  | matbas0 |  | 
						
							| 23 | 21 22 | syl |  | 
						
							| 24 | 19 23 | eqtrid |  | 
						
							| 25 | 24 | mpteq1d |  | 
						
							| 26 |  | mpt0 |  | 
						
							| 27 | 25 26 | eqtrdi |  | 
						
							| 28 | 17 27 | eqtr4d |  | 
						
							| 29 | 16 28 | sylbir |  | 
						
							| 30 | 15 29 | pm2.61i |  |