| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elfzofz |  | 
						
							| 2 |  | elfzuz2 |  | 
						
							| 3 |  | elnn0uz |  | 
						
							| 4 |  | zcn |  | 
						
							| 5 | 4 | anim1i |  | 
						
							| 6 |  | elnnnn0 |  | 
						
							| 7 | 5 6 | sylibr |  | 
						
							| 8 | 7 | expcom |  | 
						
							| 9 | 3 8 | sylbir |  | 
						
							| 10 | 1 2 9 | 3syl |  | 
						
							| 11 | 10 | impcom |  | 
						
							| 12 |  | 1nn0 |  | 
						
							| 13 | 12 | a1i |  | 
						
							| 14 |  | nnnn0 |  | 
						
							| 15 |  | nnge1 |  | 
						
							| 16 | 13 14 15 | 3jca |  | 
						
							| 17 | 11 16 | syl |  | 
						
							| 18 |  | elfz2nn0 |  | 
						
							| 19 | 17 18 | sylibr |  | 
						
							| 20 |  | fzossrbm1 |  | 
						
							| 21 | 20 | adantr |  | 
						
							| 22 |  | fzossfz |  | 
						
							| 23 | 21 22 | sstrdi |  | 
						
							| 24 |  | simpr |  | 
						
							| 25 | 23 24 | jca |  | 
						
							| 26 |  | ssel2 |  | 
						
							| 27 |  | elfzubelfz |  | 
						
							| 28 | 25 26 27 | 3syl |  | 
						
							| 29 | 19 28 | jca |  | 
						
							| 30 |  | elfzodifsumelfzo |  | 
						
							| 31 | 29 24 30 | sylc |  |