| Step | Hyp | Ref | Expression | 
						
							| 1 |  | preimageiingt.x |  | 
						
							| 2 |  | preimageiingt.b |  | 
						
							| 3 |  | preimageiingt.c |  | 
						
							| 4 |  | simpllr |  | 
						
							| 5 | 3 | adantr |  | 
						
							| 6 |  | nnrecre |  | 
						
							| 7 | 6 | adantl |  | 
						
							| 8 | 5 7 | resubcld |  | 
						
							| 9 | 8 | rexrd |  | 
						
							| 10 | 9 | ad4ant14 |  | 
						
							| 11 | 3 | rexrd |  | 
						
							| 12 | 11 | ad3antrrr |  | 
						
							| 13 | 2 | ad2antrr |  | 
						
							| 14 |  | nnrp |  | 
						
							| 15 |  | rpreccl |  | 
						
							| 16 | 14 15 | syl |  | 
						
							| 17 | 16 | adantl |  | 
						
							| 18 | 5 17 | ltsubrpd |  | 
						
							| 19 | 18 | ad4ant14 |  | 
						
							| 20 |  | simplr |  | 
						
							| 21 | 10 12 13 19 20 | xrltletrd |  | 
						
							| 22 | 4 21 | jca |  | 
						
							| 23 |  | rabid |  | 
						
							| 24 | 22 23 | sylibr |  | 
						
							| 25 | 24 | ralrimiva |  | 
						
							| 26 |  | vex |  | 
						
							| 27 |  | eliin |  | 
						
							| 28 | 26 27 | ax-mp |  | 
						
							| 29 | 25 28 | sylibr |  | 
						
							| 30 | 29 | ex |  | 
						
							| 31 | 30 | ex |  | 
						
							| 32 | 1 31 | ralrimi |  | 
						
							| 33 |  | nfcv |  | 
						
							| 34 |  | nfrab1 |  | 
						
							| 35 | 33 34 | nfiin |  | 
						
							| 36 | 35 | rabssf |  | 
						
							| 37 | 32 36 | sylibr |  | 
						
							| 38 |  | nnn0 |  | 
						
							| 39 |  | iinrab |  | 
						
							| 40 | 38 39 | ax-mp |  | 
						
							| 41 | 40 | a1i |  | 
						
							| 42 | 9 | ad4ant13 |  | 
						
							| 43 | 2 | ad2antrr |  | 
						
							| 44 |  | simpr |  | 
						
							| 45 | 42 43 44 | xrltled |  | 
						
							| 46 | 45 | ex |  | 
						
							| 47 | 46 | ralimdva |  | 
						
							| 48 | 47 | imp |  | 
						
							| 49 |  | nfv |  | 
						
							| 50 |  | nfra1 |  | 
						
							| 51 | 49 50 | nfan |  | 
						
							| 52 | 3 | ad2antrr |  | 
						
							| 53 | 2 | adantr |  | 
						
							| 54 | 51 52 53 | xrralrecnnge |  | 
						
							| 55 | 48 54 | mpbird |  | 
						
							| 56 | 55 | ex |  | 
						
							| 57 | 56 | ex |  | 
						
							| 58 | 1 57 | ralrimi |  | 
						
							| 59 |  | ss2rab |  | 
						
							| 60 | 58 59 | sylibr |  | 
						
							| 61 | 41 60 | eqsstrd |  | 
						
							| 62 | 37 61 | eqssd |  |