| Step | Hyp | Ref | Expression | 
						
							| 1 |  | fnse.1 |  | 
						
							| 2 |  | fnse.2 |  | 
						
							| 3 |  | fnse.3 |  | 
						
							| 4 |  | fnse.4 |  | 
						
							| 5 | 2 | ffvelcdmda |  | 
						
							| 6 |  | seex |  | 
						
							| 7 | 3 5 6 | syl2an2r |  | 
						
							| 8 |  | snex |  | 
						
							| 9 |  | unexg |  | 
						
							| 10 | 7 8 9 | sylancl |  | 
						
							| 11 |  | imaeq2 |  | 
						
							| 12 | 11 | eleq1d |  | 
						
							| 13 | 12 | imbi2d |  | 
						
							| 14 | 13 4 | vtoclg |  | 
						
							| 15 | 14 | impcom |  | 
						
							| 16 | 10 15 | syldan |  | 
						
							| 17 |  | inss2 |  | 
						
							| 18 |  | vex |  | 
						
							| 19 | 18 | eliniseg |  | 
						
							| 20 | 19 | elv |  | 
						
							| 21 |  | fveq2 |  | 
						
							| 22 |  | fveq2 |  | 
						
							| 23 | 21 22 | breqan12d |  | 
						
							| 24 | 21 22 | eqeqan12d |  | 
						
							| 25 |  | breq12 |  | 
						
							| 26 | 24 25 | anbi12d |  | 
						
							| 27 | 23 26 | orbi12d |  | 
						
							| 28 | 27 1 | brab2a |  | 
						
							| 29 | 2 | ffvelcdmda |  | 
						
							| 30 | 29 | adantrr |  | 
						
							| 31 |  | breq1 |  | 
						
							| 32 | 31 | elrab3 |  | 
						
							| 33 | 30 32 | syl |  | 
						
							| 34 | 33 | biimprd |  | 
						
							| 35 |  | simpl |  | 
						
							| 36 |  | fvex |  | 
						
							| 37 | 36 | elsn |  | 
						
							| 38 | 35 37 | sylibr |  | 
						
							| 39 | 38 | a1i |  | 
						
							| 40 | 34 39 | orim12d |  | 
						
							| 41 |  | elun |  | 
						
							| 42 | 40 41 | imbitrrdi |  | 
						
							| 43 |  | simprl |  | 
						
							| 44 | 42 43 | jctild |  | 
						
							| 45 | 2 | ffnd |  | 
						
							| 46 | 45 | adantr |  | 
						
							| 47 |  | elpreima |  | 
						
							| 48 | 46 47 | syl |  | 
						
							| 49 | 44 48 | sylibrd |  | 
						
							| 50 | 49 | expimpd |  | 
						
							| 51 | 28 50 | biimtrid |  | 
						
							| 52 | 20 51 | biimtrid |  | 
						
							| 53 | 52 | ssrdv |  | 
						
							| 54 | 17 53 | sstrid |  | 
						
							| 55 | 54 | adantr |  | 
						
							| 56 | 16 55 | ssexd |  | 
						
							| 57 | 56 | ralrimiva |  | 
						
							| 58 |  | dfse2 |  | 
						
							| 59 | 57 58 | sylibr |  |