| Step | Hyp | Ref | Expression | 
						
							| 1 |  | resttop |  | 
						
							| 2 |  | islly |  | 
						
							| 3 | 2 | baib |  | 
						
							| 4 | 1 3 | syl |  | 
						
							| 5 |  | vex |  | 
						
							| 6 | 5 | inex1 |  | 
						
							| 7 | 6 | a1i |  | 
						
							| 8 |  | elrest |  | 
						
							| 9 |  | simpr |  | 
						
							| 10 | 9 | raleqdv |  | 
						
							| 11 |  | rexin |  | 
						
							| 12 |  | vex |  | 
						
							| 13 | 12 | inex1 |  | 
						
							| 14 | 13 | a1i |  | 
						
							| 15 |  | elrest |  | 
						
							| 16 | 15 | ad2antrr |  | 
						
							| 17 |  | 3anass |  | 
						
							| 18 |  | simpr |  | 
						
							| 19 |  | simpllr |  | 
						
							| 20 | 18 19 | sseq12d |  | 
						
							| 21 |  | velpw |  | 
						
							| 22 |  | inss2 |  | 
						
							| 23 | 22 | biantru |  | 
						
							| 24 |  | ssin |  | 
						
							| 25 | 23 24 | bitri |  | 
						
							| 26 | 20 21 25 | 3bitr4g |  | 
						
							| 27 | 18 | eleq2d |  | 
						
							| 28 |  | simplr |  | 
						
							| 29 | 28 | elin2d |  | 
						
							| 30 | 29 | biantrud |  | 
						
							| 31 |  | elin |  | 
						
							| 32 | 30 31 | bitr4di |  | 
						
							| 33 | 27 32 | bitr4d |  | 
						
							| 34 | 18 | oveq2d |  | 
						
							| 35 |  | simp-4l |  | 
						
							| 36 | 22 | a1i |  | 
						
							| 37 |  | simplr |  | 
						
							| 38 | 37 | ad2antrr |  | 
						
							| 39 |  | restabs |  | 
						
							| 40 | 35 36 38 39 | syl3anc |  | 
						
							| 41 | 34 40 | eqtrd |  | 
						
							| 42 | 41 | eleq1d |  | 
						
							| 43 | 26 33 42 | 3anbi123d |  | 
						
							| 44 | 17 43 | bitr3id |  | 
						
							| 45 | 14 16 44 | rexxfr2d |  | 
						
							| 46 | 11 45 | bitrid |  | 
						
							| 47 | 46 | ralbidva |  | 
						
							| 48 | 10 47 | bitrd |  | 
						
							| 49 | 7 8 48 | ralxfr2d |  | 
						
							| 50 | 4 49 | bitrd |  |