| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elfz2 |  | 
						
							| 2 |  | zsubcl |  | 
						
							| 3 | 2 | 3adant1 |  | 
						
							| 4 | 3 | adantr |  | 
						
							| 5 | 1 4 | sylbi |  | 
						
							| 6 | 5 | adantr |  | 
						
							| 7 |  | elfzonelfzo |  | 
						
							| 8 | 6 7 | syl |  | 
						
							| 9 |  | elfz2nn0 |  | 
						
							| 10 |  | nn0cn |  | 
						
							| 11 |  | nn0cn |  | 
						
							| 12 |  | elfzelz |  | 
						
							| 13 |  | zcn |  | 
						
							| 14 |  | subcl |  | 
						
							| 15 | 14 | ancoms |  | 
						
							| 16 | 15 | addridd |  | 
						
							| 17 | 16 | eqcomd |  | 
						
							| 18 | 17 | adantl |  | 
						
							| 19 |  | simprr |  | 
						
							| 20 |  | simpl |  | 
						
							| 21 | 20 | adantl |  | 
						
							| 22 |  | simpl |  | 
						
							| 23 | 19 21 22 | npncan3d |  | 
						
							| 24 | 23 | eqcomd |  | 
						
							| 25 | 18 24 | oveq12d |  | 
						
							| 26 | 25 | ex |  | 
						
							| 27 | 12 13 26 | 3syl |  | 
						
							| 28 | 27 | com12 |  | 
						
							| 29 | 10 11 28 | syl2an |  | 
						
							| 30 | 29 | 3adant3 |  | 
						
							| 31 | 9 30 | sylbi |  | 
						
							| 32 | 31 | imp |  | 
						
							| 33 | 32 | eleq2d |  | 
						
							| 34 | 33 | biimpa |  | 
						
							| 35 |  | 0zd |  | 
						
							| 36 |  | elfz2 |  | 
						
							| 37 |  | zsubcl |  | 
						
							| 38 | 37 | ancoms |  | 
						
							| 39 | 38 | 3adant2 |  | 
						
							| 40 | 39 | adantr |  | 
						
							| 41 | 36 40 | sylbi |  | 
						
							| 42 | 41 | adantl |  | 
						
							| 43 | 6 35 42 | 3jca |  | 
						
							| 44 | 43 | adantr |  | 
						
							| 45 |  | fzosubel2 |  | 
						
							| 46 | 34 44 45 | syl2anc |  | 
						
							| 47 | 46 | ex |  | 
						
							| 48 | 8 47 | syld |  |