| Step | Hyp | Ref | Expression | 
						
							| 1 |  | iscyg.1 |  | 
						
							| 2 |  | iscyg.2 |  | 
						
							| 3 |  | iscyg3.e |  | 
						
							| 4 |  | cyggeninv.n |  | 
						
							| 5 | 1 2 3 | iscyggen2 |  | 
						
							| 6 | 5 | simprbda |  | 
						
							| 7 | 1 4 | grpinvcl |  | 
						
							| 8 | 6 7 | syldan |  | 
						
							| 9 | 5 | simplbda |  | 
						
							| 10 |  | oveq1 |  | 
						
							| 11 | 10 | eqeq2d |  | 
						
							| 12 | 11 | cbvrexvw |  | 
						
							| 13 |  | znegcl |  | 
						
							| 14 | 13 | adantl |  | 
						
							| 15 |  | simpr |  | 
						
							| 16 | 15 | zcnd |  | 
						
							| 17 | 16 | negnegd |  | 
						
							| 18 | 17 | oveq1d |  | 
						
							| 19 |  | simplll |  | 
						
							| 20 | 6 | ad2antrr |  | 
						
							| 21 | 1 2 4 | mulgneg2 |  | 
						
							| 22 | 19 14 20 21 | syl3anc |  | 
						
							| 23 | 18 22 | eqtr3d |  | 
						
							| 24 |  | oveq1 |  | 
						
							| 25 | 24 | rspceeqv |  | 
						
							| 26 | 14 23 25 | syl2anc |  | 
						
							| 27 |  | eqeq1 |  | 
						
							| 28 | 27 | rexbidv |  | 
						
							| 29 | 26 28 | syl5ibrcom |  | 
						
							| 30 | 29 | rexlimdva |  | 
						
							| 31 | 12 30 | biimtrid |  | 
						
							| 32 | 31 | ralimdva |  | 
						
							| 33 | 9 32 | mpd |  | 
						
							| 34 | 1 2 3 | iscyggen2 |  | 
						
							| 35 | 34 | adantr |  | 
						
							| 36 | 8 33 35 | mpbir2and |  |