| Step | Hyp | Ref | Expression | 
						
							| 1 |  | idn1 |  |-  (. A e. V ->. A e. V ). | 
						
							| 2 |  | csbconstg |  |-  ( A e. V -> [_ A / x ]_ _V = _V ) | 
						
							| 3 | 1 2 | e1a |  |-  (. A e. V ->. [_ A / x ]_ _V = _V ). | 
						
							| 4 |  | xpeq2 |  |-  ( [_ A / x ]_ _V = _V -> ( [_ A / x ]_ C X. [_ A / x ]_ _V ) = ( [_ A / x ]_ C X. _V ) ) | 
						
							| 5 | 3 4 | e1a |  |-  (. A e. V ->. ( [_ A / x ]_ C X. [_ A / x ]_ _V ) = ( [_ A / x ]_ C X. _V ) ). | 
						
							| 6 |  | csbxp |  |-  [_ A / x ]_ ( C X. _V ) = ( [_ A / x ]_ C X. [_ A / x ]_ _V ) | 
						
							| 7 | 6 | a1i |  |-  ( A e. V -> [_ A / x ]_ ( C X. _V ) = ( [_ A / x ]_ C X. [_ A / x ]_ _V ) ) | 
						
							| 8 | 1 7 | e1a |  |-  (. A e. V ->. [_ A / x ]_ ( C X. _V ) = ( [_ A / x ]_ C X. [_ A / x ]_ _V ) ). | 
						
							| 9 |  | eqeq2 |  |-  ( ( [_ A / x ]_ C X. [_ A / x ]_ _V ) = ( [_ A / x ]_ C X. _V ) -> ( [_ A / x ]_ ( C X. _V ) = ( [_ A / x ]_ C X. [_ A / x ]_ _V ) <-> [_ A / x ]_ ( C X. _V ) = ( [_ A / x ]_ C X. _V ) ) ) | 
						
							| 10 | 9 | biimpd |  |-  ( ( [_ A / x ]_ C X. [_ A / x ]_ _V ) = ( [_ A / x ]_ C X. _V ) -> ( [_ A / x ]_ ( C X. _V ) = ( [_ A / x ]_ C X. [_ A / x ]_ _V ) -> [_ A / x ]_ ( C X. _V ) = ( [_ A / x ]_ C X. _V ) ) ) | 
						
							| 11 | 5 8 10 | e11 |  |-  (. A e. V ->. [_ A / x ]_ ( C X. _V ) = ( [_ A / x ]_ C X. _V ) ). | 
						
							| 12 |  | ineq2 |  |-  ( [_ A / x ]_ ( C X. _V ) = ( [_ A / x ]_ C X. _V ) -> ( [_ A / x ]_ B i^i [_ A / x ]_ ( C X. _V ) ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) ) | 
						
							| 13 | 11 12 | e1a |  |-  (. A e. V ->. ( [_ A / x ]_ B i^i [_ A / x ]_ ( C X. _V ) ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) ). | 
						
							| 14 |  | csbin |  |-  [_ A / x ]_ ( B i^i ( C X. _V ) ) = ( [_ A / x ]_ B i^i [_ A / x ]_ ( C X. _V ) ) | 
						
							| 15 | 14 | a1i |  |-  ( A e. V -> [_ A / x ]_ ( B i^i ( C X. _V ) ) = ( [_ A / x ]_ B i^i [_ A / x ]_ ( C X. _V ) ) ) | 
						
							| 16 | 1 15 | e1a |  |-  (. A e. V ->. [_ A / x ]_ ( B i^i ( C X. _V ) ) = ( [_ A / x ]_ B i^i [_ A / x ]_ ( C X. _V ) ) ). | 
						
							| 17 |  | eqeq2 |  |-  ( ( [_ A / x ]_ B i^i [_ A / x ]_ ( C X. _V ) ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) -> ( [_ A / x ]_ ( B i^i ( C X. _V ) ) = ( [_ A / x ]_ B i^i [_ A / x ]_ ( C X. _V ) ) <-> [_ A / x ]_ ( B i^i ( C X. _V ) ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) ) ) | 
						
							| 18 | 17 | biimpd |  |-  ( ( [_ A / x ]_ B i^i [_ A / x ]_ ( C X. _V ) ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) -> ( [_ A / x ]_ ( B i^i ( C X. _V ) ) = ( [_ A / x ]_ B i^i [_ A / x ]_ ( C X. _V ) ) -> [_ A / x ]_ ( B i^i ( C X. _V ) ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) ) ) | 
						
							| 19 | 13 16 18 | e11 |  |-  (. A e. V ->. [_ A / x ]_ ( B i^i ( C X. _V ) ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) ). | 
						
							| 20 |  | df-res |  |-  ( B |` C ) = ( B i^i ( C X. _V ) ) | 
						
							| 21 | 20 | ax-gen |  |-  A. x ( B |` C ) = ( B i^i ( C X. _V ) ) | 
						
							| 22 |  | csbeq2 |  |-  ( A. x ( B |` C ) = ( B i^i ( C X. _V ) ) -> [_ A / x ]_ ( B |` C ) = [_ A / x ]_ ( B i^i ( C X. _V ) ) ) | 
						
							| 23 | 22 | a1i |  |-  ( A e. V -> ( A. x ( B |` C ) = ( B i^i ( C X. _V ) ) -> [_ A / x ]_ ( B |` C ) = [_ A / x ]_ ( B i^i ( C X. _V ) ) ) ) | 
						
							| 24 | 1 21 23 | e10 |  |-  (. A e. V ->. [_ A / x ]_ ( B |` C ) = [_ A / x ]_ ( B i^i ( C X. _V ) ) ). | 
						
							| 25 |  | eqeq2 |  |-  ( [_ A / x ]_ ( B i^i ( C X. _V ) ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) -> ( [_ A / x ]_ ( B |` C ) = [_ A / x ]_ ( B i^i ( C X. _V ) ) <-> [_ A / x ]_ ( B |` C ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) ) ) | 
						
							| 26 | 25 | biimpd |  |-  ( [_ A / x ]_ ( B i^i ( C X. _V ) ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) -> ( [_ A / x ]_ ( B |` C ) = [_ A / x ]_ ( B i^i ( C X. _V ) ) -> [_ A / x ]_ ( B |` C ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) ) ) | 
						
							| 27 | 19 24 26 | e11 |  |-  (. A e. V ->. [_ A / x ]_ ( B |` C ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) ). | 
						
							| 28 |  | df-res |  |-  ( [_ A / x ]_ B |` [_ A / x ]_ C ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) | 
						
							| 29 |  | eqeq2 |  |-  ( ( [_ A / x ]_ B |` [_ A / x ]_ C ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) -> ( [_ A / x ]_ ( B |` C ) = ( [_ A / x ]_ B |` [_ A / x ]_ C ) <-> [_ A / x ]_ ( B |` C ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) ) ) | 
						
							| 30 | 29 | biimprcd |  |-  ( [_ A / x ]_ ( B |` C ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) -> ( ( [_ A / x ]_ B |` [_ A / x ]_ C ) = ( [_ A / x ]_ B i^i ( [_ A / x ]_ C X. _V ) ) -> [_ A / x ]_ ( B |` C ) = ( [_ A / x ]_ B |` [_ A / x ]_ C ) ) ) | 
						
							| 31 | 27 28 30 | e10 |  |-  (. A e. V ->. [_ A / x ]_ ( B |` C ) = ( [_ A / x ]_ B |` [_ A / x ]_ C ) ). | 
						
							| 32 | 31 | in1 |  |-  ( A e. V -> [_ A / x ]_ ( B |` C ) = ( [_ A / x ]_ B |` [_ A / x ]_ C ) ) |