| Step | Hyp | Ref | Expression | 
						
							| 1 |  | vcm.1 |  | 
						
							| 2 |  | vcm.2 |  | 
						
							| 3 |  | vcm.3 |  | 
						
							| 4 |  | vcm.4 |  | 
						
							| 5 | 1 | vcgrp |  | 
						
							| 6 | 5 | adantr |  | 
						
							| 7 |  | neg1cn |  | 
						
							| 8 | 1 2 3 | vccl |  | 
						
							| 9 | 7 8 | mp3an2 |  | 
						
							| 10 |  | eqid |  | 
						
							| 11 | 3 10 | grporid |  | 
						
							| 12 | 6 9 11 | syl2anc |  | 
						
							| 13 |  | simpr |  | 
						
							| 14 | 3 4 | grpoinvcl |  | 
						
							| 15 | 5 14 | sylan |  | 
						
							| 16 | 3 | grpoass |  | 
						
							| 17 | 6 9 13 15 16 | syl13anc |  | 
						
							| 18 | 1 2 3 | vcidOLD |  | 
						
							| 19 | 18 | oveq2d |  | 
						
							| 20 |  | ax-1cn |  | 
						
							| 21 |  | 1pneg1e0 |  | 
						
							| 22 | 20 7 21 | addcomli |  | 
						
							| 23 | 22 | oveq1i |  | 
						
							| 24 | 1 2 3 | vcdir |  | 
						
							| 25 | 7 24 | mp3anr1 |  | 
						
							| 26 | 20 25 | mpanr1 |  | 
						
							| 27 | 1 2 3 10 | vc0 |  | 
						
							| 28 | 23 26 27 | 3eqtr3a |  | 
						
							| 29 | 19 28 | eqtr3d |  | 
						
							| 30 | 29 | oveq1d |  | 
						
							| 31 | 17 30 | eqtr3d |  | 
						
							| 32 | 3 10 4 | grporinv |  | 
						
							| 33 | 5 32 | sylan |  | 
						
							| 34 | 33 | oveq2d |  | 
						
							| 35 | 31 34 | eqtr3d |  | 
						
							| 36 | 3 10 | grpolid |  | 
						
							| 37 | 6 15 36 | syl2anc |  | 
						
							| 38 | 35 37 | eqtr3d |  | 
						
							| 39 | 12 38 | eqtr3d |  |