| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elbigo |  | 
						
							| 2 |  | df-3an |  | 
						
							| 3 | 1 2 | bitri |  | 
						
							| 4 |  | reex |  | 
						
							| 5 | 4 4 | pm3.2i |  | 
						
							| 6 | 5 | a1i |  | 
						
							| 7 |  | simpl |  | 
						
							| 8 | 7 | adantl |  | 
						
							| 9 |  | sstr2 |  | 
						
							| 10 | 9 | adantld |  | 
						
							| 11 | 10 | adantl |  | 
						
							| 12 | 11 | impcom |  | 
						
							| 13 |  | elpm2r |  | 
						
							| 14 | 6 8 12 13 | syl12anc |  | 
						
							| 15 |  | simpl |  | 
						
							| 16 |  | elpm2r |  | 
						
							| 17 | 6 15 16 | syl2anc |  | 
						
							| 18 |  | ibar |  | 
						
							| 19 | 18 | bicomd |  | 
						
							| 20 | 14 17 19 | syl2anc |  | 
						
							| 21 | 3 20 | bitrid |  | 
						
							| 22 |  | elin |  | 
						
							| 23 |  | fdm |  | 
						
							| 24 | 23 | ad2antrl |  | 
						
							| 25 | 24 | ad2antrr |  | 
						
							| 26 | 25 | eleq2d |  | 
						
							| 27 | 26 | anbi1d |  | 
						
							| 28 |  | elicopnf |  | 
						
							| 29 | 28 | ad3antlr |  | 
						
							| 30 | 12 | ad2antrr |  | 
						
							| 31 | 30 | sselda |  | 
						
							| 32 | 31 | biantrurd |  | 
						
							| 33 | 29 32 | bitr4d |  | 
						
							| 34 | 33 | pm5.32da |  | 
						
							| 35 | 27 34 | bitrd |  | 
						
							| 36 | 22 35 | bitrid |  | 
						
							| 37 | 36 | imbi1d |  | 
						
							| 38 |  | impexp |  | 
						
							| 39 | 37 38 | bitrdi |  | 
						
							| 40 | 39 | ralbidv2 |  | 
						
							| 41 | 40 | rexbidva |  | 
						
							| 42 | 41 | rexbidva |  | 
						
							| 43 | 21 42 | bitrd |  |