| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ressmulgnn.1 |  |-  H = ( G |`s A ) | 
						
							| 2 |  | ressmulgnn.2 |  |-  A C_ ( Base ` G ) | 
						
							| 3 |  | ressmulgnn.3 |  |-  .* = ( .g ` G ) | 
						
							| 4 |  | ressmulgnn.4 |  |-  I = ( invg ` G ) | 
						
							| 5 |  | ressmulgnn0.4 |  |-  ( 0g ` G ) = ( 0g ` H ) | 
						
							| 6 |  | simpr |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N e. NN ) -> N e. NN ) | 
						
							| 7 |  | simplr |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N e. NN ) -> X e. A ) | 
						
							| 8 | 1 2 3 4 | ressmulgnn |  |-  ( ( N e. NN /\ X e. A ) -> ( N ( .g ` H ) X ) = ( N .* X ) ) | 
						
							| 9 | 6 7 8 | syl2anc |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N e. NN ) -> ( N ( .g ` H ) X ) = ( N .* X ) ) | 
						
							| 10 |  | simplr |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N = 0 ) -> X e. A ) | 
						
							| 11 |  | eqid |  |-  ( Base ` G ) = ( Base ` G ) | 
						
							| 12 | 1 11 | ressbas2 |  |-  ( A C_ ( Base ` G ) -> A = ( Base ` H ) ) | 
						
							| 13 | 2 12 | ax-mp |  |-  A = ( Base ` H ) | 
						
							| 14 |  | eqid |  |-  ( .g ` H ) = ( .g ` H ) | 
						
							| 15 | 13 5 14 | mulg0 |  |-  ( X e. A -> ( 0 ( .g ` H ) X ) = ( 0g ` G ) ) | 
						
							| 16 | 10 15 | syl |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N = 0 ) -> ( 0 ( .g ` H ) X ) = ( 0g ` G ) ) | 
						
							| 17 |  | simpr |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N = 0 ) -> N = 0 ) | 
						
							| 18 | 17 | oveq1d |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N = 0 ) -> ( N ( .g ` H ) X ) = ( 0 ( .g ` H ) X ) ) | 
						
							| 19 | 2 10 | sselid |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N = 0 ) -> X e. ( Base ` G ) ) | 
						
							| 20 |  | eqid |  |-  ( 0g ` G ) = ( 0g ` G ) | 
						
							| 21 | 11 20 3 | mulg0 |  |-  ( X e. ( Base ` G ) -> ( 0 .* X ) = ( 0g ` G ) ) | 
						
							| 22 | 19 21 | syl |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N = 0 ) -> ( 0 .* X ) = ( 0g ` G ) ) | 
						
							| 23 | 16 18 22 | 3eqtr4d |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N = 0 ) -> ( N ( .g ` H ) X ) = ( 0 .* X ) ) | 
						
							| 24 | 17 | oveq1d |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N = 0 ) -> ( N .* X ) = ( 0 .* X ) ) | 
						
							| 25 | 23 24 | eqtr4d |  |-  ( ( ( N e. NN0 /\ X e. A ) /\ N = 0 ) -> ( N ( .g ` H ) X ) = ( N .* X ) ) | 
						
							| 26 |  | elnn0 |  |-  ( N e. NN0 <-> ( N e. NN \/ N = 0 ) ) | 
						
							| 27 | 26 | biimpi |  |-  ( N e. NN0 -> ( N e. NN \/ N = 0 ) ) | 
						
							| 28 | 27 | adantr |  |-  ( ( N e. NN0 /\ X e. A ) -> ( N e. NN \/ N = 0 ) ) | 
						
							| 29 | 9 25 28 | mpjaodan |  |-  ( ( N e. NN0 /\ X e. A ) -> ( N ( .g ` H ) X ) = ( N .* X ) ) |