| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dipfval.1 |  | 
						
							| 2 |  | dipfval.2 |  | 
						
							| 3 |  | dipfval.4 |  | 
						
							| 4 |  | dipfval.6 |  | 
						
							| 5 |  | dipfval.7 |  | 
						
							| 6 | 1 2 3 4 5 | ipval2 |  | 
						
							| 7 | 6 | oveq2d |  | 
						
							| 8 |  | simp1 |  | 
						
							| 9 | 1 2 | nvgcl |  | 
						
							| 10 | 1 4 | nvcl |  | 
						
							| 11 | 8 9 10 | syl2anc |  | 
						
							| 12 | 11 | recnd |  | 
						
							| 13 | 12 | sqcld |  | 
						
							| 14 |  | neg1cn |  | 
						
							| 15 | 1 3 | nvscl |  | 
						
							| 16 | 14 15 | mp3an2 |  | 
						
							| 17 | 16 | 3adant2 |  | 
						
							| 18 | 1 2 | nvgcl |  | 
						
							| 19 | 17 18 | syld3an3 |  | 
						
							| 20 | 1 4 | nvcl |  | 
						
							| 21 | 8 19 20 | syl2anc |  | 
						
							| 22 | 21 | recnd |  | 
						
							| 23 | 22 | sqcld |  | 
						
							| 24 | 13 23 | subcld |  | 
						
							| 25 |  | ax-icn |  | 
						
							| 26 | 1 3 | nvscl |  | 
						
							| 27 | 25 26 | mp3an2 |  | 
						
							| 28 | 27 | 3adant2 |  | 
						
							| 29 | 1 2 | nvgcl |  | 
						
							| 30 | 28 29 | syld3an3 |  | 
						
							| 31 | 1 4 | nvcl |  | 
						
							| 32 | 8 30 31 | syl2anc |  | 
						
							| 33 | 32 | recnd |  | 
						
							| 34 | 33 | sqcld |  | 
						
							| 35 |  | negicn |  | 
						
							| 36 | 1 3 | nvscl |  | 
						
							| 37 | 35 36 | mp3an2 |  | 
						
							| 38 | 37 | 3adant2 |  | 
						
							| 39 | 1 2 | nvgcl |  | 
						
							| 40 | 38 39 | syld3an3 |  | 
						
							| 41 | 1 4 | nvcl |  | 
						
							| 42 | 8 40 41 | syl2anc |  | 
						
							| 43 | 42 | recnd |  | 
						
							| 44 | 43 | sqcld |  | 
						
							| 45 | 34 44 | subcld |  | 
						
							| 46 |  | mulcl |  | 
						
							| 47 | 25 45 46 | sylancr |  | 
						
							| 48 | 24 47 | addcld |  | 
						
							| 49 |  | 4cn |  | 
						
							| 50 |  | 4ne0 |  | 
						
							| 51 |  | divcan2 |  | 
						
							| 52 | 49 50 51 | mp3an23 |  | 
						
							| 53 | 48 52 | syl |  | 
						
							| 54 | 7 53 | eqtrd |  |