| Step | Hyp | Ref | Expression | 
						
							| 1 |  | nvdif.1 |  | 
						
							| 2 |  | nvdif.2 |  | 
						
							| 3 |  | nvdif.4 |  | 
						
							| 4 |  | nvdif.6 |  | 
						
							| 5 |  | simp1 |  | 
						
							| 6 |  | neg1cn |  | 
						
							| 7 | 6 | a1i |  | 
						
							| 8 |  | simp3 |  | 
						
							| 9 | 1 3 | nvscl |  | 
						
							| 10 | 6 9 | mp3an2 |  | 
						
							| 11 | 10 | 3adant3 |  | 
						
							| 12 | 1 2 3 | nvdi |  | 
						
							| 13 | 5 7 8 11 12 | syl13anc |  | 
						
							| 14 | 1 3 | nvnegneg |  | 
						
							| 15 | 14 | 3adant3 |  | 
						
							| 16 | 15 | oveq2d |  | 
						
							| 17 | 1 3 | nvscl |  | 
						
							| 18 | 6 17 | mp3an2 |  | 
						
							| 19 | 18 | 3adant2 |  | 
						
							| 20 |  | simp2 |  | 
						
							| 21 | 1 2 | nvcom |  | 
						
							| 22 | 5 19 20 21 | syl3anc |  | 
						
							| 23 | 13 16 22 | 3eqtrd |  | 
						
							| 24 | 23 | fveq2d |  | 
						
							| 25 | 1 2 | nvgcl |  | 
						
							| 26 | 5 8 11 25 | syl3anc |  | 
						
							| 27 | 1 3 4 | nvm1 |  | 
						
							| 28 | 5 26 27 | syl2anc |  | 
						
							| 29 | 24 28 | eqtr3d |  |