| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elfzolt2 |  | 
						
							| 2 |  | elfzoelz |  | 
						
							| 3 | 2 | zred |  | 
						
							| 4 |  | elfzoel2 |  | 
						
							| 5 | 4 | zred |  | 
						
							| 6 | 3 5 | ltnled |  | 
						
							| 7 | 1 6 | mpbid |  | 
						
							| 8 | 7 | adantr |  | 
						
							| 9 |  | elfzonn0 |  | 
						
							| 10 | 9 | adantr |  | 
						
							| 11 |  | simpr |  | 
						
							| 12 |  | eldifsn |  | 
						
							| 13 | 10 11 12 | sylanbrc |  | 
						
							| 14 |  | dfn2 |  | 
						
							| 15 | 13 14 | eleqtrrdi |  | 
						
							| 16 |  | dvdsle |  | 
						
							| 17 | 4 15 16 | syl2an2r |  | 
						
							| 18 | 8 17 | mtod |  | 
						
							| 19 | 18 | ex |  | 
						
							| 20 | 19 | necon4ad |  | 
						
							| 21 |  | dvds0 |  | 
						
							| 22 | 4 21 | syl |  | 
						
							| 23 |  | breq2 |  | 
						
							| 24 | 22 23 | syl5ibrcom |  | 
						
							| 25 | 20 24 | impbid |  |