| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							resinf1o | 
							 |-  ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) : ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) -1-1-onto-> ( -u 1 [,] 1 )  | 
						
						
							| 2 | 
							
								
							 | 
							f1ocnv | 
							 |-  ( ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) : ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) -1-1-onto-> ( -u 1 [,] 1 ) -> `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) : ( -u 1 [,] 1 ) -1-1-onto-> ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) )  | 
						
						
							| 3 | 
							
								
							 | 
							f1of | 
							 |-  ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) : ( -u 1 [,] 1 ) -1-1-onto-> ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) -> `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) : ( -u 1 [,] 1 ) --> ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) )  | 
						
						
							| 4 | 
							
								1 2 3
							 | 
							mp2b | 
							 |-  `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) : ( -u 1 [,] 1 ) --> ( -u ( _pi / 2 ) [,] ( _pi / 2 ) )  | 
						
						
							| 5 | 
							
								4
							 | 
							ffvelcdmi | 
							 |-  ( A e. ( -u 1 [,] 1 ) -> ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) e. ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) )  | 
						
						
							| 6 | 
							
								5
							 | 
							fvresd | 
							 |-  ( A e. ( -u 1 [,] 1 ) -> ( ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) ) = ( sin ` ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) ) )  | 
						
						
							| 7 | 
							
								
							 | 
							f1ocnvfv2 | 
							 |-  ( ( ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) : ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) -1-1-onto-> ( -u 1 [,] 1 ) /\ A e. ( -u 1 [,] 1 ) ) -> ( ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) ) = A )  | 
						
						
							| 8 | 
							
								1 7
							 | 
							mpan | 
							 |-  ( A e. ( -u 1 [,] 1 ) -> ( ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) ) = A )  | 
						
						
							| 9 | 
							
								6 8
							 | 
							eqtr3d | 
							 |-  ( A e. ( -u 1 [,] 1 ) -> ( sin ` ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) ) = A )  | 
						
						
							| 10 | 
							
								9
							 | 
							fveq2d | 
							 |-  ( A e. ( -u 1 [,] 1 ) -> ( arcsin ` ( sin ` ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) ) ) = ( arcsin ` A ) )  | 
						
						
							| 11 | 
							
								
							 | 
							reasinsin | 
							 |-  ( ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) e. ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) -> ( arcsin ` ( sin ` ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) ) ) = ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) )  | 
						
						
							| 12 | 
							
								5 11
							 | 
							syl | 
							 |-  ( A e. ( -u 1 [,] 1 ) -> ( arcsin ` ( sin ` ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) ) ) = ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) )  | 
						
						
							| 13 | 
							
								10 12
							 | 
							eqtr3d | 
							 |-  ( A e. ( -u 1 [,] 1 ) -> ( arcsin ` A ) = ( `' ( sin |` ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) ) ` A ) )  | 
						
						
							| 14 | 
							
								13 5
							 | 
							eqeltrd | 
							 |-  ( A e. ( -u 1 [,] 1 ) -> ( arcsin ` A ) e. ( -u ( _pi / 2 ) [,] ( _pi / 2 ) ) )  |