| Step | Hyp | Ref | Expression | 
						
							| 1 |  | sseq1 |  | 
						
							| 2 |  | fveq2 |  | 
						
							| 3 | 2 | sseq1d |  | 
						
							| 4 | 1 3 | imbi12d |  | 
						
							| 5 |  | sseq2 |  | 
						
							| 6 |  | fveq2 |  | 
						
							| 7 | 6 | sseq2d |  | 
						
							| 8 | 5 7 | imbi12d |  | 
						
							| 9 | 4 8 | cbvral2vw |  | 
						
							| 10 |  | inss1 |  | 
						
							| 11 |  | inss2 |  | 
						
							| 12 |  | elpwi |  | 
						
							| 13 | 11 12 | sstrid |  | 
						
							| 14 |  | vex |  | 
						
							| 15 | 14 | inex2 |  | 
						
							| 16 | 15 | elpw |  | 
						
							| 17 | 13 16 | sylibr |  | 
						
							| 18 | 17 | ad2antll |  | 
						
							| 19 |  | simprl |  | 
						
							| 20 |  | simpl |  | 
						
							| 21 |  | sseq1 |  | 
						
							| 22 |  | fveq2 |  | 
						
							| 23 | 22 | sseq1d |  | 
						
							| 24 | 21 23 | imbi12d |  | 
						
							| 25 |  | sseq2 |  | 
						
							| 26 |  | fveq2 |  | 
						
							| 27 | 26 | sseq2d |  | 
						
							| 28 | 25 27 | imbi12d |  | 
						
							| 29 | 24 28 | rspc2va |  | 
						
							| 30 | 18 19 20 29 | syl21anc |  | 
						
							| 31 | 10 30 | mpi |  | 
						
							| 32 |  | simprr |  | 
						
							| 33 |  | sseq2 |  | 
						
							| 34 |  | fveq2 |  | 
						
							| 35 | 34 | sseq2d |  | 
						
							| 36 | 33 35 | imbi12d |  | 
						
							| 37 | 24 36 | rspc2va |  | 
						
							| 38 | 18 32 20 37 | syl21anc |  | 
						
							| 39 | 11 38 | mpi |  | 
						
							| 40 | 31 39 | ssind |  | 
						
							| 41 | 40 | ralrimivva |  | 
						
							| 42 |  | dfss |  | 
						
							| 43 |  | fveq2 |  | 
						
							| 44 | 43 | adantl |  | 
						
							| 45 |  | ineq1 |  | 
						
							| 46 | 45 | fveq2d |  | 
						
							| 47 | 2 | ineq1d |  | 
						
							| 48 | 46 47 | sseq12d |  | 
						
							| 49 |  | ineq2 |  | 
						
							| 50 | 49 | fveq2d |  | 
						
							| 51 | 6 | ineq2d |  | 
						
							| 52 | 50 51 | sseq12d |  | 
						
							| 53 | 48 52 | rspc2va |  | 
						
							| 54 | 53 | ancoms |  | 
						
							| 55 |  | inss2 |  | 
						
							| 56 | 54 55 | sstrdi |  | 
						
							| 57 | 56 | adantr |  | 
						
							| 58 | 44 57 | eqsstrd |  | 
						
							| 59 | 58 | ex |  | 
						
							| 60 | 42 59 | biimtrid |  | 
						
							| 61 | 60 | ralrimivva |  | 
						
							| 62 | 41 61 | impbii |  | 
						
							| 63 | 9 62 | bitri |  |