| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elfzo2 |  | 
						
							| 2 |  | elnnuz |  | 
						
							| 3 |  | nnnn0 |  | 
						
							| 4 | 3 | adantr |  | 
						
							| 5 | 4 | adantr |  | 
						
							| 6 |  | nngt0 |  | 
						
							| 7 |  | 0red |  | 
						
							| 8 |  | nnre |  | 
						
							| 9 | 8 | adantl |  | 
						
							| 10 |  | zre |  | 
						
							| 11 | 10 | adantr |  | 
						
							| 12 |  | lttr |  | 
						
							| 13 | 7 9 11 12 | syl3anc |  | 
						
							| 14 |  | elnnz |  | 
						
							| 15 | 14 | simplbi2 |  | 
						
							| 16 | 15 | adantr |  | 
						
							| 17 | 13 16 | syld |  | 
						
							| 18 | 17 | exp4b |  | 
						
							| 19 | 18 | com13 |  | 
						
							| 20 | 6 19 | mpcom |  | 
						
							| 21 | 20 | imp31 |  | 
						
							| 22 |  | simpr |  | 
						
							| 23 | 5 21 22 | 3jca |  | 
						
							| 24 | 23 | exp31 |  | 
						
							| 25 | 2 24 | sylbir |  | 
						
							| 26 | 25 | 3imp |  | 
						
							| 27 |  | elfzo0 |  | 
						
							| 28 | 26 27 | sylibr |  | 
						
							| 29 |  | nnne0 |  | 
						
							| 30 | 2 29 | sylbir |  | 
						
							| 31 | 30 | 3ad2ant1 |  | 
						
							| 32 | 28 31 | jca |  | 
						
							| 33 | 1 32 | sylbi |  | 
						
							| 34 |  | elnnne0 |  | 
						
							| 35 |  | nnge1 |  | 
						
							| 36 | 34 35 | sylbir |  | 
						
							| 37 | 36 | 3ad2antl1 |  | 
						
							| 38 |  | simpl3 |  | 
						
							| 39 |  | nn0z |  | 
						
							| 40 | 39 | adantr |  | 
						
							| 41 |  | 1zzd |  | 
						
							| 42 |  | nnz |  | 
						
							| 43 | 42 | adantl |  | 
						
							| 44 | 40 41 43 | 3jca |  | 
						
							| 45 | 44 | 3adant3 |  | 
						
							| 46 | 45 | adantr |  | 
						
							| 47 |  | elfzo |  | 
						
							| 48 | 46 47 | syl |  | 
						
							| 49 | 37 38 48 | mpbir2and |  | 
						
							| 50 | 27 49 | sylanb |  | 
						
							| 51 | 33 50 | impbii |  |