| Step | Hyp | Ref | Expression | 
						
							| 1 |  | satefv |  | 
						
							| 2 |  | incom |  | 
						
							| 3 |  | sqxpexg |  | 
						
							| 4 |  | inex1g |  | 
						
							| 5 | 3 4 | syl |  | 
						
							| 6 | 2 5 | eqeltrid |  | 
						
							| 7 | 6 | ancli |  | 
						
							| 8 | 7 | adantr |  | 
						
							| 9 |  | satom |  | 
						
							| 10 | 8 9 | syl |  | 
						
							| 11 | 10 | fveq1d |  | 
						
							| 12 |  | satfun |  | 
						
							| 13 | 8 12 | syl |  | 
						
							| 14 | 13 | ffund |  | 
						
							| 15 | 10 | eqcomd |  | 
						
							| 16 | 15 | funeqd |  | 
						
							| 17 | 14 16 | mpbird |  | 
						
							| 18 |  | peano1 |  | 
						
							| 19 | 18 | a1i |  | 
						
							| 20 | 18 | a1i |  | 
						
							| 21 |  | satfdmfmla |  | 
						
							| 22 | 6 20 21 | mpd3an23 |  | 
						
							| 23 | 22 | eqcomd |  | 
						
							| 24 | 23 | eleq2d |  | 
						
							| 25 | 24 | biimpa |  | 
						
							| 26 |  | eqid |  | 
						
							| 27 | 26 | fviunfun |  | 
						
							| 28 | 17 19 25 27 | syl3anc |  | 
						
							| 29 | 11 28 | eqtrd |  | 
						
							| 30 |  | simpl |  | 
						
							| 31 | 6 | adantr |  | 
						
							| 32 |  | simpr |  | 
						
							| 33 |  | eqid |  | 
						
							| 34 | 33 | satfv0fvfmla0 |  | 
						
							| 35 | 30 31 32 34 | syl3anc |  | 
						
							| 36 |  | elmapi |  | 
						
							| 37 |  | simpl |  | 
						
							| 38 |  | fmla0xp |  | 
						
							| 39 | 38 | eleq2i |  | 
						
							| 40 |  | elxp |  | 
						
							| 41 | 39 40 | bitri |  | 
						
							| 42 |  | xp1st |  | 
						
							| 43 | 42 | ad2antll |  | 
						
							| 44 |  | vex |  | 
						
							| 45 |  | vex |  | 
						
							| 46 | 44 45 | op2ndd |  | 
						
							| 47 | 46 | fveq2d |  | 
						
							| 48 | 47 | eleq1d |  | 
						
							| 49 | 48 | adantr |  | 
						
							| 50 | 43 49 | mpbird |  | 
						
							| 51 | 50 | exlimivv |  | 
						
							| 52 | 41 51 | sylbi |  | 
						
							| 53 | 52 | ad2antll |  | 
						
							| 54 | 37 53 | ffvelcdmd |  | 
						
							| 55 |  | xp2nd |  | 
						
							| 56 | 55 | ad2antll |  | 
						
							| 57 | 46 | fveq2d |  | 
						
							| 58 | 57 | eleq1d |  | 
						
							| 59 | 58 | adantr |  | 
						
							| 60 | 56 59 | mpbird |  | 
						
							| 61 | 60 | exlimivv |  | 
						
							| 62 | 41 61 | sylbi |  | 
						
							| 63 | 62 | ad2antll |  | 
						
							| 64 | 37 63 | ffvelcdmd |  | 
						
							| 65 | 54 64 | jca |  | 
						
							| 66 | 65 | ex |  | 
						
							| 67 | 36 66 | syl |  | 
						
							| 68 | 67 | impcom |  | 
						
							| 69 |  | brinxp |  | 
						
							| 70 | 69 | bicomd |  | 
						
							| 71 | 68 70 | syl |  | 
						
							| 72 |  | fvex |  | 
						
							| 73 | 72 | epeli |  | 
						
							| 74 | 71 73 | bitrdi |  | 
						
							| 75 | 74 | rabbidva |  | 
						
							| 76 | 35 75 | eqtrd |  | 
						
							| 77 | 29 76 | eqtrd |  | 
						
							| 78 | 1 77 | eqtrd |  |