| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dstfrv.1 |  | 
						
							| 2 |  | dstfrv.2 |  | 
						
							| 3 |  | 1red |  | 
						
							| 4 | 1 2 | rrvvf |  | 
						
							| 5 | 4 | ffvelcdmda |  | 
						
							| 6 | 3 5 | ifcld |  | 
						
							| 7 |  | breq2 |  | 
						
							| 8 |  | breq2 |  | 
						
							| 9 |  | 1le1 |  | 
						
							| 10 | 9 | a1i |  | 
						
							| 11 | 3 5 | lenltd |  | 
						
							| 12 | 11 | biimpar |  | 
						
							| 13 | 7 8 10 12 | ifbothda |  | 
						
							| 14 |  | flge1nn |  | 
						
							| 15 | 6 13 14 | syl2anc |  | 
						
							| 16 | 15 | peano2nnd |  | 
						
							| 17 | 1 | adantr |  | 
						
							| 18 | 2 | adantr |  | 
						
							| 19 | 16 | nnred |  | 
						
							| 20 |  | simpr |  | 
						
							| 21 |  | breq2 |  | 
						
							| 22 |  | breq2 |  | 
						
							| 23 | 5 | adantr |  | 
						
							| 24 |  | 1red |  | 
						
							| 25 |  | simpr |  | 
						
							| 26 | 23 24 25 | ltled |  | 
						
							| 27 | 5 | leidd |  | 
						
							| 28 | 27 | adantr |  | 
						
							| 29 | 21 22 26 28 | ifbothda |  | 
						
							| 30 |  | fllep1 |  | 
						
							| 31 | 6 30 | syl |  | 
						
							| 32 | 5 6 19 29 31 | letrd |  | 
						
							| 33 | 17 18 19 20 32 | dstfrvel |  | 
						
							| 34 |  | oveq2 |  | 
						
							| 35 | 34 | eleq2d |  | 
						
							| 36 | 35 | rspcev |  | 
						
							| 37 | 16 33 36 | syl2anc |  | 
						
							| 38 | 37 | ex |  | 
						
							| 39 | 1 | adantr |  | 
						
							| 40 | 2 | adantr |  | 
						
							| 41 |  | simpr |  | 
						
							| 42 | 41 | nnred |  | 
						
							| 43 | 39 40 42 | orvclteel |  | 
						
							| 44 |  | elunii |  | 
						
							| 45 | 44 | expcom |  | 
						
							| 46 | 43 45 | syl |  | 
						
							| 47 | 46 | rexlimdva |  | 
						
							| 48 | 38 47 | impbid |  | 
						
							| 49 |  | eliun |  | 
						
							| 50 | 48 49 | bitr4di |  | 
						
							| 51 | 50 | eqrdv |  | 
						
							| 52 |  | ovex |  | 
						
							| 53 | 52 | dfiun3 |  | 
						
							| 54 | 51 53 | eqtr2di |  |