| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elex |  | 
						
							| 2 |  | eqid |  | 
						
							| 3 |  | eqid |  | 
						
							| 4 | 2 3 | xmssym |  | 
						
							| 5 | 4 | 3expb |  | 
						
							| 6 | 5 | ralrimivva |  | 
						
							| 7 |  | simpl |  | 
						
							| 8 |  | simpr3 |  | 
						
							| 9 |  | equid |  | 
						
							| 10 | 2 3 | xmseq0 |  | 
						
							| 11 | 9 10 | mpbiri |  | 
						
							| 12 | 7 8 8 11 | syl3anc |  | 
						
							| 13 | 12 | eqeq2d |  | 
						
							| 14 | 2 3 | xmseq0 |  | 
						
							| 15 | 14 | 3adant3r3 |  | 
						
							| 16 | 13 15 | bitrd |  | 
						
							| 17 | 16 | biimpd |  | 
						
							| 18 | 17 | ralrimivvva |  | 
						
							| 19 | 6 18 | jca |  | 
						
							| 20 |  | eqid |  | 
						
							| 21 | 2 3 20 | istrkgc |  | 
						
							| 22 | 1 19 21 | sylanbrc |  |