| Step | Hyp | Ref | Expression | 
						
							| 1 |  | caovdig.1 |  |-  ( ( ph /\ ( x e. K /\ y e. S /\ z e. S ) ) -> ( x G ( y F z ) ) = ( ( x G y ) H ( x G z ) ) ) | 
						
							| 2 | 1 | ralrimivvva |  |-  ( ph -> A. x e. K A. y e. S A. z e. S ( x G ( y F z ) ) = ( ( x G y ) H ( x G z ) ) ) | 
						
							| 3 |  | oveq1 |  |-  ( x = A -> ( x G ( y F z ) ) = ( A G ( y F z ) ) ) | 
						
							| 4 |  | oveq1 |  |-  ( x = A -> ( x G y ) = ( A G y ) ) | 
						
							| 5 |  | oveq1 |  |-  ( x = A -> ( x G z ) = ( A G z ) ) | 
						
							| 6 | 4 5 | oveq12d |  |-  ( x = A -> ( ( x G y ) H ( x G z ) ) = ( ( A G y ) H ( A G z ) ) ) | 
						
							| 7 | 3 6 | eqeq12d |  |-  ( x = A -> ( ( x G ( y F z ) ) = ( ( x G y ) H ( x G z ) ) <-> ( A G ( y F z ) ) = ( ( A G y ) H ( A G z ) ) ) ) | 
						
							| 8 |  | oveq1 |  |-  ( y = B -> ( y F z ) = ( B F z ) ) | 
						
							| 9 | 8 | oveq2d |  |-  ( y = B -> ( A G ( y F z ) ) = ( A G ( B F z ) ) ) | 
						
							| 10 |  | oveq2 |  |-  ( y = B -> ( A G y ) = ( A G B ) ) | 
						
							| 11 | 10 | oveq1d |  |-  ( y = B -> ( ( A G y ) H ( A G z ) ) = ( ( A G B ) H ( A G z ) ) ) | 
						
							| 12 | 9 11 | eqeq12d |  |-  ( y = B -> ( ( A G ( y F z ) ) = ( ( A G y ) H ( A G z ) ) <-> ( A G ( B F z ) ) = ( ( A G B ) H ( A G z ) ) ) ) | 
						
							| 13 |  | oveq2 |  |-  ( z = C -> ( B F z ) = ( B F C ) ) | 
						
							| 14 | 13 | oveq2d |  |-  ( z = C -> ( A G ( B F z ) ) = ( A G ( B F C ) ) ) | 
						
							| 15 |  | oveq2 |  |-  ( z = C -> ( A G z ) = ( A G C ) ) | 
						
							| 16 | 15 | oveq2d |  |-  ( z = C -> ( ( A G B ) H ( A G z ) ) = ( ( A G B ) H ( A G C ) ) ) | 
						
							| 17 | 14 16 | eqeq12d |  |-  ( z = C -> ( ( A G ( B F z ) ) = ( ( A G B ) H ( A G z ) ) <-> ( A G ( B F C ) ) = ( ( A G B ) H ( A G C ) ) ) ) | 
						
							| 18 | 7 12 17 | rspc3v |  |-  ( ( A e. K /\ B e. S /\ C e. S ) -> ( A. x e. K A. y e. S A. z e. S ( x G ( y F z ) ) = ( ( x G y ) H ( x G z ) ) -> ( A G ( B F C ) ) = ( ( A G B ) H ( A G C ) ) ) ) | 
						
							| 19 | 2 18 | mpan9 |  |-  ( ( ph /\ ( A e. K /\ B e. S /\ C e. S ) ) -> ( A G ( B F C ) ) = ( ( A G B ) H ( A G C ) ) ) |