| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mat1dim.a |  | 
						
							| 2 |  | mat1dim.b |  | 
						
							| 3 |  | mat1dim.o |  | 
						
							| 4 |  | snfi |  | 
						
							| 5 | 4 | a1i |  | 
						
							| 6 | 5 | anim2i |  | 
						
							| 7 | 6 | ancomd |  | 
						
							| 8 |  | eqid |  | 
						
							| 9 | 1 8 | mat0op |  | 
						
							| 10 | 7 9 | syl |  | 
						
							| 11 |  | simpr |  | 
						
							| 12 |  | fvexd |  | 
						
							| 13 |  | eqid |  | 
						
							| 14 |  | eqidd |  | 
						
							| 15 |  | eqidd |  | 
						
							| 16 | 13 14 15 | mposn |  | 
						
							| 17 | 3 | eqcomi |  | 
						
							| 18 | 17 | opeq1i |  | 
						
							| 19 | 18 | sneqi |  | 
						
							| 20 | 16 19 | eqtrdi |  | 
						
							| 21 | 11 11 12 20 | syl3anc |  | 
						
							| 22 | 10 21 | eqtrd |  |