| Step | Hyp | Ref | Expression | 
						
							| 1 |  | funcoppc.o |  | 
						
							| 2 |  | funcoppc.p |  | 
						
							| 3 |  | funcoppc.f |  | 
						
							| 4 |  | eqid |  | 
						
							| 5 | 1 4 | oppcbas |  | 
						
							| 6 |  | eqid |  | 
						
							| 7 | 2 6 | oppcbas |  | 
						
							| 8 |  | eqid |  | 
						
							| 9 |  | eqid |  | 
						
							| 10 |  | eqid |  | 
						
							| 11 |  | eqid |  | 
						
							| 12 |  | eqid |  | 
						
							| 13 |  | eqid |  | 
						
							| 14 |  | df-br |  | 
						
							| 15 | 3 14 | sylib |  | 
						
							| 16 |  | funcrcl |  | 
						
							| 17 | 15 16 | syl |  | 
						
							| 18 | 17 | simpld |  | 
						
							| 19 | 1 | oppccat |  | 
						
							| 20 | 18 19 | syl |  | 
						
							| 21 | 2 | oppccat |  | 
						
							| 22 | 17 21 | simpl2im |  | 
						
							| 23 | 4 6 3 | funcf1 |  | 
						
							| 24 | 4 3 | funcfn2 |  | 
						
							| 25 |  | tposfn |  | 
						
							| 26 | 24 25 | syl |  | 
						
							| 27 |  | eqid |  | 
						
							| 28 |  | eqid |  | 
						
							| 29 | 3 | adantr |  | 
						
							| 30 |  | simprr |  | 
						
							| 31 |  | simprl |  | 
						
							| 32 | 4 27 28 29 30 31 | funcf2 |  | 
						
							| 33 |  | ovtpos |  | 
						
							| 34 | 33 | feq1i |  | 
						
							| 35 | 27 1 | oppchom |  | 
						
							| 36 | 28 2 | oppchom |  | 
						
							| 37 | 35 36 | feq23i |  | 
						
							| 38 | 34 37 | bitri |  | 
						
							| 39 | 32 38 | sylibr |  | 
						
							| 40 |  | eqid |  | 
						
							| 41 |  | eqid |  | 
						
							| 42 | 3 | adantr |  | 
						
							| 43 |  | simpr |  | 
						
							| 44 | 4 40 41 42 43 | funcid |  | 
						
							| 45 |  | ovtpos |  | 
						
							| 46 | 45 | a1i |  | 
						
							| 47 | 1 40 | oppcid |  | 
						
							| 48 | 18 47 | syl |  | 
						
							| 49 | 48 | adantr |  | 
						
							| 50 | 49 | fveq1d |  | 
						
							| 51 | 46 50 | fveq12d |  | 
						
							| 52 | 2 41 | oppcid |  | 
						
							| 53 | 17 52 | simpl2im |  | 
						
							| 54 | 53 | adantr |  | 
						
							| 55 | 54 | fveq1d |  | 
						
							| 56 | 44 51 55 | 3eqtr4d |  | 
						
							| 57 |  | eqid |  | 
						
							| 58 |  | eqid |  | 
						
							| 59 | 3 | 3ad2ant1 |  | 
						
							| 60 |  | simp23 |  | 
						
							| 61 |  | simp22 |  | 
						
							| 62 |  | simp21 |  | 
						
							| 63 |  | simp3r |  | 
						
							| 64 | 27 1 | oppchom |  | 
						
							| 65 | 63 64 | eleqtrdi |  | 
						
							| 66 |  | simp3l |  | 
						
							| 67 | 66 35 | eleqtrdi |  | 
						
							| 68 | 4 27 57 58 59 60 61 62 65 67 | funcco |  | 
						
							| 69 | 4 57 1 62 61 60 | oppcco |  | 
						
							| 70 | 69 | fveq2d |  | 
						
							| 71 | 23 | 3ad2ant1 |  | 
						
							| 72 | 71 62 | ffvelcdmd |  | 
						
							| 73 | 71 61 | ffvelcdmd |  | 
						
							| 74 | 71 60 | ffvelcdmd |  | 
						
							| 75 | 6 58 2 72 73 74 | oppcco |  | 
						
							| 76 | 68 70 75 | 3eqtr4d |  | 
						
							| 77 |  | ovtpos |  | 
						
							| 78 | 77 | fveq1i |  | 
						
							| 79 |  | ovtpos |  | 
						
							| 80 | 79 | fveq1i |  | 
						
							| 81 | 33 | fveq1i |  | 
						
							| 82 | 80 81 | oveq12i |  | 
						
							| 83 | 76 78 82 | 3eqtr4g |  | 
						
							| 84 | 5 7 8 9 10 11 12 13 20 22 23 26 39 56 83 | isfuncd |  |