| Step | Hyp | Ref | Expression | 
						
							| 1 |  | sdrginvcl.i |  | 
						
							| 2 |  | sdrginvcl.0 |  | 
						
							| 3 |  | issdrg |  | 
						
							| 4 | 3 | biimpi |  | 
						
							| 5 | 4 | 3ad2ant1 |  | 
						
							| 6 | 5 | simp3d |  | 
						
							| 7 |  | simp2 |  | 
						
							| 8 | 5 | simp2d |  | 
						
							| 9 |  | eqid |  | 
						
							| 10 | 9 | subrgbas |  | 
						
							| 11 | 8 10 | syl |  | 
						
							| 12 | 7 11 | eleqtrd |  | 
						
							| 13 |  | simp3 |  | 
						
							| 14 | 9 2 | subrg0 |  | 
						
							| 15 | 8 14 | syl |  | 
						
							| 16 | 13 15 | neeqtrd |  | 
						
							| 17 |  | eqid |  | 
						
							| 18 |  | eqid |  | 
						
							| 19 |  | eqid |  | 
						
							| 20 | 17 18 19 | drnginvrcl |  | 
						
							| 21 | 6 12 16 20 | syl3anc |  | 
						
							| 22 |  | eqid |  | 
						
							| 23 | 17 22 18 | drngunit |  | 
						
							| 24 | 23 | biimpar |  | 
						
							| 25 | 6 12 16 24 | syl12anc |  | 
						
							| 26 | 9 1 22 19 | subrginv |  | 
						
							| 27 | 8 25 26 | syl2anc |  | 
						
							| 28 | 21 27 11 | 3eltr4d |  |