| Step | Hyp | Ref | Expression | 
						
							| 1 |  | deg1addle.y |  |-  Y = ( Poly1 ` R ) | 
						
							| 2 |  | deg1addle.d |  |-  D = ( deg1 ` R ) | 
						
							| 3 |  | deg1addle.r |  |-  ( ph -> R e. Ring ) | 
						
							| 4 |  | deg1invg.b |  |-  B = ( Base ` Y ) | 
						
							| 5 |  | deg1invg.n |  |-  N = ( invg ` Y ) | 
						
							| 6 |  | deg1invg.f |  |-  ( ph -> F e. B ) | 
						
							| 7 | 1 | ply1lmod |  |-  ( R e. Ring -> Y e. LMod ) | 
						
							| 8 | 3 7 | syl |  |-  ( ph -> Y e. LMod ) | 
						
							| 9 | 1 | ply1sca2 |  |-  ( _I ` R ) = ( Scalar ` Y ) | 
						
							| 10 |  | eqid |  |-  ( .s ` Y ) = ( .s ` Y ) | 
						
							| 11 |  | eqid |  |-  ( 1r ` ( _I ` R ) ) = ( 1r ` ( _I ` R ) ) | 
						
							| 12 |  | eqid |  |-  ( invg ` R ) = ( invg ` R ) | 
						
							| 13 | 12 | grpinvfvi |  |-  ( invg ` R ) = ( invg ` ( _I ` R ) ) | 
						
							| 14 | 4 5 9 10 11 13 | lmodvneg1 |  |-  ( ( Y e. LMod /\ F e. B ) -> ( ( ( invg ` R ) ` ( 1r ` ( _I ` R ) ) ) ( .s ` Y ) F ) = ( N ` F ) ) | 
						
							| 15 | 8 6 14 | syl2anc |  |-  ( ph -> ( ( ( invg ` R ) ` ( 1r ` ( _I ` R ) ) ) ( .s ` Y ) F ) = ( N ` F ) ) | 
						
							| 16 | 15 | fveq2d |  |-  ( ph -> ( D ` ( ( ( invg ` R ) ` ( 1r ` ( _I ` R ) ) ) ( .s ` Y ) F ) ) = ( D ` ( N ` F ) ) ) | 
						
							| 17 |  | eqid |  |-  ( RLReg ` R ) = ( RLReg ` R ) | 
						
							| 18 |  | fvi |  |-  ( R e. Ring -> ( _I ` R ) = R ) | 
						
							| 19 | 3 18 | syl |  |-  ( ph -> ( _I ` R ) = R ) | 
						
							| 20 | 19 | fveq2d |  |-  ( ph -> ( 1r ` ( _I ` R ) ) = ( 1r ` R ) ) | 
						
							| 21 | 20 | fveq2d |  |-  ( ph -> ( ( invg ` R ) ` ( 1r ` ( _I ` R ) ) ) = ( ( invg ` R ) ` ( 1r ` R ) ) ) | 
						
							| 22 |  | eqid |  |-  ( Unit ` R ) = ( Unit ` R ) | 
						
							| 23 | 17 22 | unitrrg |  |-  ( R e. Ring -> ( Unit ` R ) C_ ( RLReg ` R ) ) | 
						
							| 24 | 3 23 | syl |  |-  ( ph -> ( Unit ` R ) C_ ( RLReg ` R ) ) | 
						
							| 25 |  | eqid |  |-  ( 1r ` R ) = ( 1r ` R ) | 
						
							| 26 | 22 25 | 1unit |  |-  ( R e. Ring -> ( 1r ` R ) e. ( Unit ` R ) ) | 
						
							| 27 | 22 12 | unitnegcl |  |-  ( ( R e. Ring /\ ( 1r ` R ) e. ( Unit ` R ) ) -> ( ( invg ` R ) ` ( 1r ` R ) ) e. ( Unit ` R ) ) | 
						
							| 28 | 3 26 27 | syl2anc2 |  |-  ( ph -> ( ( invg ` R ) ` ( 1r ` R ) ) e. ( Unit ` R ) ) | 
						
							| 29 | 24 28 | sseldd |  |-  ( ph -> ( ( invg ` R ) ` ( 1r ` R ) ) e. ( RLReg ` R ) ) | 
						
							| 30 | 21 29 | eqeltrd |  |-  ( ph -> ( ( invg ` R ) ` ( 1r ` ( _I ` R ) ) ) e. ( RLReg ` R ) ) | 
						
							| 31 | 1 2 3 4 17 10 30 6 | deg1vsca |  |-  ( ph -> ( D ` ( ( ( invg ` R ) ` ( 1r ` ( _I ` R ) ) ) ( .s ` Y ) F ) ) = ( D ` F ) ) | 
						
							| 32 | 16 31 | eqtr3d |  |-  ( ph -> ( D ` ( N ` F ) ) = ( D ` F ) ) |