| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ixx.1 |  | 
						
							| 2 |  | ixxun.2 |  | 
						
							| 3 |  | ixxun.3 |  | 
						
							| 4 |  | ixxun.4 |  | 
						
							| 5 |  | ixxun.5 |  | 
						
							| 6 |  | ixxun.6 |  | 
						
							| 7 |  | elun |  | 
						
							| 8 |  | simpl1 |  | 
						
							| 9 |  | simpl2 |  | 
						
							| 10 | 1 | elixx1 |  | 
						
							| 11 | 8 9 10 | syl2anc |  | 
						
							| 12 | 11 | biimpa |  | 
						
							| 13 | 12 | simp1d |  | 
						
							| 14 | 12 | simp2d |  | 
						
							| 15 | 12 | simp3d |  | 
						
							| 16 |  | simplrr |  | 
						
							| 17 | 9 | adantr |  | 
						
							| 18 |  | simpl3 |  | 
						
							| 19 | 18 | adantr |  | 
						
							| 20 | 13 17 19 5 | syl3anc |  | 
						
							| 21 | 15 16 20 | mp2and |  | 
						
							| 22 | 13 14 21 | 3jca |  | 
						
							| 23 | 2 | elixx1 |  | 
						
							| 24 | 9 18 23 | syl2anc |  | 
						
							| 25 | 24 | biimpa |  | 
						
							| 26 | 25 | simp1d |  | 
						
							| 27 |  | simplrl |  | 
						
							| 28 | 25 | simp2d |  | 
						
							| 29 | 8 | adantr |  | 
						
							| 30 | 9 | adantr |  | 
						
							| 31 | 29 30 26 6 | syl3anc |  | 
						
							| 32 | 27 28 31 | mp2and |  | 
						
							| 33 | 25 | simp3d |  | 
						
							| 34 | 26 32 33 | 3jca |  | 
						
							| 35 | 22 34 | jaodan |  | 
						
							| 36 | 4 | elixx1 |  | 
						
							| 37 | 8 18 36 | syl2anc |  | 
						
							| 38 | 37 | biimpar |  | 
						
							| 39 | 35 38 | syldan |  | 
						
							| 40 |  | exmid |  | 
						
							| 41 | 37 | biimpa |  | 
						
							| 42 | 41 | simp1d |  | 
						
							| 43 | 41 | simp2d |  | 
						
							| 44 | 42 43 | jca |  | 
						
							| 45 |  | df-3an |  | 
						
							| 46 | 11 45 | bitrdi |  | 
						
							| 47 | 46 | adantr |  | 
						
							| 48 | 44 47 | mpbirand |  | 
						
							| 49 |  | 3anan12 |  | 
						
							| 50 | 24 49 | bitrdi |  | 
						
							| 51 | 50 | adantr |  | 
						
							| 52 | 41 | simp3d |  | 
						
							| 53 | 42 52 | jca |  | 
						
							| 54 | 53 | biantrud |  | 
						
							| 55 | 9 | adantr |  | 
						
							| 56 | 55 42 3 | syl2anc |  | 
						
							| 57 | 51 54 56 | 3bitr2d |  | 
						
							| 58 | 48 57 | orbi12d |  | 
						
							| 59 | 40 58 | mpbiri |  | 
						
							| 60 | 39 59 | impbida |  | 
						
							| 61 | 7 60 | bitrid |  | 
						
							| 62 | 61 | eqrdv |  |