| Step | Hyp | Ref | Expression | 
						
							| 1 |  | m1expcl |  |-  ( X e. ZZ -> ( -u 1 ^ X ) e. ZZ ) | 
						
							| 2 | 1 | zcnd |  |-  ( X e. ZZ -> ( -u 1 ^ X ) e. CC ) | 
						
							| 3 | 2 | adantr |  |-  ( ( X e. ZZ /\ Y e. ZZ ) -> ( -u 1 ^ X ) e. CC ) | 
						
							| 4 |  | m1expcl |  |-  ( Y e. ZZ -> ( -u 1 ^ Y ) e. ZZ ) | 
						
							| 5 | 4 | zcnd |  |-  ( Y e. ZZ -> ( -u 1 ^ Y ) e. CC ) | 
						
							| 6 | 5 | adantl |  |-  ( ( X e. ZZ /\ Y e. ZZ ) -> ( -u 1 ^ Y ) e. CC ) | 
						
							| 7 |  | neg1cn |  |-  -u 1 e. CC | 
						
							| 8 |  | neg1ne0 |  |-  -u 1 =/= 0 | 
						
							| 9 |  | expne0i |  |-  ( ( -u 1 e. CC /\ -u 1 =/= 0 /\ Y e. ZZ ) -> ( -u 1 ^ Y ) =/= 0 ) | 
						
							| 10 | 7 8 9 | mp3an12 |  |-  ( Y e. ZZ -> ( -u 1 ^ Y ) =/= 0 ) | 
						
							| 11 | 10 | adantl |  |-  ( ( X e. ZZ /\ Y e. ZZ ) -> ( -u 1 ^ Y ) =/= 0 ) | 
						
							| 12 | 3 6 11 | divrecd |  |-  ( ( X e. ZZ /\ Y e. ZZ ) -> ( ( -u 1 ^ X ) / ( -u 1 ^ Y ) ) = ( ( -u 1 ^ X ) x. ( 1 / ( -u 1 ^ Y ) ) ) ) | 
						
							| 13 |  | m1expcl2 |  |-  ( Y e. ZZ -> ( -u 1 ^ Y ) e. { -u 1 , 1 } ) | 
						
							| 14 |  | elpri |  |-  ( ( -u 1 ^ Y ) e. { -u 1 , 1 } -> ( ( -u 1 ^ Y ) = -u 1 \/ ( -u 1 ^ Y ) = 1 ) ) | 
						
							| 15 |  | ax-1cn |  |-  1 e. CC | 
						
							| 16 |  | ax-1ne0 |  |-  1 =/= 0 | 
						
							| 17 |  | divneg2 |  |-  ( ( 1 e. CC /\ 1 e. CC /\ 1 =/= 0 ) -> -u ( 1 / 1 ) = ( 1 / -u 1 ) ) | 
						
							| 18 | 15 15 16 17 | mp3an |  |-  -u ( 1 / 1 ) = ( 1 / -u 1 ) | 
						
							| 19 |  | 1div1e1 |  |-  ( 1 / 1 ) = 1 | 
						
							| 20 | 19 | negeqi |  |-  -u ( 1 / 1 ) = -u 1 | 
						
							| 21 | 18 20 | eqtr3i |  |-  ( 1 / -u 1 ) = -u 1 | 
						
							| 22 |  | oveq2 |  |-  ( ( -u 1 ^ Y ) = -u 1 -> ( 1 / ( -u 1 ^ Y ) ) = ( 1 / -u 1 ) ) | 
						
							| 23 |  | id |  |-  ( ( -u 1 ^ Y ) = -u 1 -> ( -u 1 ^ Y ) = -u 1 ) | 
						
							| 24 | 21 22 23 | 3eqtr4a |  |-  ( ( -u 1 ^ Y ) = -u 1 -> ( 1 / ( -u 1 ^ Y ) ) = ( -u 1 ^ Y ) ) | 
						
							| 25 |  | oveq2 |  |-  ( ( -u 1 ^ Y ) = 1 -> ( 1 / ( -u 1 ^ Y ) ) = ( 1 / 1 ) ) | 
						
							| 26 |  | id |  |-  ( ( -u 1 ^ Y ) = 1 -> ( -u 1 ^ Y ) = 1 ) | 
						
							| 27 | 19 25 26 | 3eqtr4a |  |-  ( ( -u 1 ^ Y ) = 1 -> ( 1 / ( -u 1 ^ Y ) ) = ( -u 1 ^ Y ) ) | 
						
							| 28 | 24 27 | jaoi |  |-  ( ( ( -u 1 ^ Y ) = -u 1 \/ ( -u 1 ^ Y ) = 1 ) -> ( 1 / ( -u 1 ^ Y ) ) = ( -u 1 ^ Y ) ) | 
						
							| 29 | 13 14 28 | 3syl |  |-  ( Y e. ZZ -> ( 1 / ( -u 1 ^ Y ) ) = ( -u 1 ^ Y ) ) | 
						
							| 30 | 29 | adantl |  |-  ( ( X e. ZZ /\ Y e. ZZ ) -> ( 1 / ( -u 1 ^ Y ) ) = ( -u 1 ^ Y ) ) | 
						
							| 31 | 30 | oveq2d |  |-  ( ( X e. ZZ /\ Y e. ZZ ) -> ( ( -u 1 ^ X ) x. ( 1 / ( -u 1 ^ Y ) ) ) = ( ( -u 1 ^ X ) x. ( -u 1 ^ Y ) ) ) | 
						
							| 32 | 12 31 | eqtrd |  |-  ( ( X e. ZZ /\ Y e. ZZ ) -> ( ( -u 1 ^ X ) / ( -u 1 ^ Y ) ) = ( ( -u 1 ^ X ) x. ( -u 1 ^ Y ) ) ) | 
						
							| 33 |  | expsub |  |-  ( ( ( -u 1 e. CC /\ -u 1 =/= 0 ) /\ ( X e. ZZ /\ Y e. ZZ ) ) -> ( -u 1 ^ ( X - Y ) ) = ( ( -u 1 ^ X ) / ( -u 1 ^ Y ) ) ) | 
						
							| 34 | 7 8 33 | mpanl12 |  |-  ( ( X e. ZZ /\ Y e. ZZ ) -> ( -u 1 ^ ( X - Y ) ) = ( ( -u 1 ^ X ) / ( -u 1 ^ Y ) ) ) | 
						
							| 35 |  | expaddz |  |-  ( ( ( -u 1 e. CC /\ -u 1 =/= 0 ) /\ ( X e. ZZ /\ Y e. ZZ ) ) -> ( -u 1 ^ ( X + Y ) ) = ( ( -u 1 ^ X ) x. ( -u 1 ^ Y ) ) ) | 
						
							| 36 | 7 8 35 | mpanl12 |  |-  ( ( X e. ZZ /\ Y e. ZZ ) -> ( -u 1 ^ ( X + Y ) ) = ( ( -u 1 ^ X ) x. ( -u 1 ^ Y ) ) ) | 
						
							| 37 | 32 34 36 | 3eqtr4d |  |-  ( ( X e. ZZ /\ Y e. ZZ ) -> ( -u 1 ^ ( X - Y ) ) = ( -u 1 ^ ( X + Y ) ) ) |