| Step | Hyp | Ref | Expression | 
						
							| 1 |  | isfunc.b |  | 
						
							| 2 |  | isfunc.c |  | 
						
							| 3 |  | isfunc.h |  | 
						
							| 4 |  | isfunc.j |  | 
						
							| 5 |  | isfunc.1 |  | 
						
							| 6 |  | isfunc.i |  | 
						
							| 7 |  | isfunc.x |  | 
						
							| 8 |  | isfunc.o |  | 
						
							| 9 |  | isfunc.d |  | 
						
							| 10 |  | isfunc.e |  | 
						
							| 11 |  | isfuncd.1 |  | 
						
							| 12 |  | isfuncd.2 |  | 
						
							| 13 |  | isfuncd.3 |  | 
						
							| 14 |  | isfuncd.4 |  | 
						
							| 15 |  | isfuncd.5 |  | 
						
							| 16 | 1 | fvexi |  | 
						
							| 17 | 16 16 | xpex |  | 
						
							| 18 |  | fnex |  | 
						
							| 19 | 12 17 18 | sylancl |  | 
						
							| 20 |  | ovex |  | 
						
							| 21 |  | ovex |  | 
						
							| 22 | 20 21 | elmap |  | 
						
							| 23 | 13 22 | sylibr |  | 
						
							| 24 | 23 | ralrimivva |  | 
						
							| 25 |  | fveq2 |  | 
						
							| 26 |  | df-ov |  | 
						
							| 27 | 25 26 | eqtr4di |  | 
						
							| 28 |  | vex |  | 
						
							| 29 |  | vex |  | 
						
							| 30 | 28 29 | op1std |  | 
						
							| 31 | 30 | fveq2d |  | 
						
							| 32 | 28 29 | op2ndd |  | 
						
							| 33 | 32 | fveq2d |  | 
						
							| 34 | 31 33 | oveq12d |  | 
						
							| 35 |  | fveq2 |  | 
						
							| 36 |  | df-ov |  | 
						
							| 37 | 35 36 | eqtr4di |  | 
						
							| 38 | 34 37 | oveq12d |  | 
						
							| 39 | 27 38 | eleq12d |  | 
						
							| 40 | 39 | ralxp |  | 
						
							| 41 | 24 40 | sylibr |  | 
						
							| 42 |  | elixp2 |  | 
						
							| 43 | 19 12 41 42 | syl3anbrc |  | 
						
							| 44 | 15 | 3expia |  | 
						
							| 45 | 44 | 3exp2 |  | 
						
							| 46 | 45 | imp43 |  | 
						
							| 47 | 46 | ralrimivv |  | 
						
							| 48 | 47 | ralrimivva |  | 
						
							| 49 | 14 48 | jca |  | 
						
							| 50 | 49 | ralrimiva |  | 
						
							| 51 | 1 2 3 4 5 6 7 8 9 10 | isfunc |  | 
						
							| 52 | 11 43 50 51 | mpbir3and |  |