| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ixpsnval |  | 
						
							| 2 | 1 | adantl |  | 
						
							| 3 |  | csbfv2g |  | 
						
							| 4 |  | csbfv2g |  | 
						
							| 5 |  | csbvarg |  | 
						
							| 6 | 5 | fveq2d |  | 
						
							| 7 | 4 6 | eqtrd |  | 
						
							| 8 | 7 | fveq2d |  | 
						
							| 9 | 3 8 | eqtrd |  | 
						
							| 10 | 9 | adantl |  | 
						
							| 11 |  | fvexd |  | 
						
							| 12 | 11 | anim1ci |  | 
						
							| 13 |  | xpsng |  | 
						
							| 14 | 12 13 | syl |  | 
						
							| 15 | 14 | fveq1d |  | 
						
							| 16 |  | fvsng |  | 
						
							| 17 | 12 16 | syl |  | 
						
							| 18 | 15 17 | eqtrd |  | 
						
							| 19 | 18 | fveq2d |  | 
						
							| 20 | 10 19 | eqtrd |  | 
						
							| 21 |  | rlmbas |  | 
						
							| 22 | 20 21 | eqtr4di |  | 
						
							| 23 | 22 | eleq2d |  | 
						
							| 24 | 23 | anbi2d |  | 
						
							| 25 | 24 | abbidv |  | 
						
							| 26 | 2 25 | eqtrd |  |