| Step | Hyp | Ref | Expression | 
						
							| 1 |  | rngidpropd.1 |  |-  ( ph -> B = ( Base ` K ) ) | 
						
							| 2 |  | rngidpropd.2 |  |-  ( ph -> B = ( Base ` L ) ) | 
						
							| 3 |  | rngidpropd.3 |  |-  ( ( ph /\ ( x e. B /\ y e. B ) ) -> ( x ( .r ` K ) y ) = ( x ( .r ` L ) y ) ) | 
						
							| 4 |  | eqid |  |-  ( Unit ` K ) = ( Unit ` K ) | 
						
							| 5 |  | eqid |  |-  ( ( mulGrp ` K ) |`s ( Unit ` K ) ) = ( ( mulGrp ` K ) |`s ( Unit ` K ) ) | 
						
							| 6 | 4 5 | unitgrpbas |  |-  ( Unit ` K ) = ( Base ` ( ( mulGrp ` K ) |`s ( Unit ` K ) ) ) | 
						
							| 7 | 6 | a1i |  |-  ( ph -> ( Unit ` K ) = ( Base ` ( ( mulGrp ` K ) |`s ( Unit ` K ) ) ) ) | 
						
							| 8 | 1 2 3 | unitpropd |  |-  ( ph -> ( Unit ` K ) = ( Unit ` L ) ) | 
						
							| 9 |  | eqid |  |-  ( Unit ` L ) = ( Unit ` L ) | 
						
							| 10 |  | eqid |  |-  ( ( mulGrp ` L ) |`s ( Unit ` L ) ) = ( ( mulGrp ` L ) |`s ( Unit ` L ) ) | 
						
							| 11 | 9 10 | unitgrpbas |  |-  ( Unit ` L ) = ( Base ` ( ( mulGrp ` L ) |`s ( Unit ` L ) ) ) | 
						
							| 12 | 8 11 | eqtrdi |  |-  ( ph -> ( Unit ` K ) = ( Base ` ( ( mulGrp ` L ) |`s ( Unit ` L ) ) ) ) | 
						
							| 13 |  | eqid |  |-  ( Base ` K ) = ( Base ` K ) | 
						
							| 14 | 13 4 | unitss |  |-  ( Unit ` K ) C_ ( Base ` K ) | 
						
							| 15 | 14 1 | sseqtrrid |  |-  ( ph -> ( Unit ` K ) C_ B ) | 
						
							| 16 | 15 | sselda |  |-  ( ( ph /\ x e. ( Unit ` K ) ) -> x e. B ) | 
						
							| 17 | 15 | sselda |  |-  ( ( ph /\ y e. ( Unit ` K ) ) -> y e. B ) | 
						
							| 18 | 16 17 | anim12dan |  |-  ( ( ph /\ ( x e. ( Unit ` K ) /\ y e. ( Unit ` K ) ) ) -> ( x e. B /\ y e. B ) ) | 
						
							| 19 | 18 3 | syldan |  |-  ( ( ph /\ ( x e. ( Unit ` K ) /\ y e. ( Unit ` K ) ) ) -> ( x ( .r ` K ) y ) = ( x ( .r ` L ) y ) ) | 
						
							| 20 |  | fvex |  |-  ( Unit ` K ) e. _V | 
						
							| 21 |  | eqid |  |-  ( mulGrp ` K ) = ( mulGrp ` K ) | 
						
							| 22 |  | eqid |  |-  ( .r ` K ) = ( .r ` K ) | 
						
							| 23 | 21 22 | mgpplusg |  |-  ( .r ` K ) = ( +g ` ( mulGrp ` K ) ) | 
						
							| 24 | 5 23 | ressplusg |  |-  ( ( Unit ` K ) e. _V -> ( .r ` K ) = ( +g ` ( ( mulGrp ` K ) |`s ( Unit ` K ) ) ) ) | 
						
							| 25 | 20 24 | ax-mp |  |-  ( .r ` K ) = ( +g ` ( ( mulGrp ` K ) |`s ( Unit ` K ) ) ) | 
						
							| 26 | 25 | oveqi |  |-  ( x ( .r ` K ) y ) = ( x ( +g ` ( ( mulGrp ` K ) |`s ( Unit ` K ) ) ) y ) | 
						
							| 27 |  | fvex |  |-  ( Unit ` L ) e. _V | 
						
							| 28 |  | eqid |  |-  ( mulGrp ` L ) = ( mulGrp ` L ) | 
						
							| 29 |  | eqid |  |-  ( .r ` L ) = ( .r ` L ) | 
						
							| 30 | 28 29 | mgpplusg |  |-  ( .r ` L ) = ( +g ` ( mulGrp ` L ) ) | 
						
							| 31 | 10 30 | ressplusg |  |-  ( ( Unit ` L ) e. _V -> ( .r ` L ) = ( +g ` ( ( mulGrp ` L ) |`s ( Unit ` L ) ) ) ) | 
						
							| 32 | 27 31 | ax-mp |  |-  ( .r ` L ) = ( +g ` ( ( mulGrp ` L ) |`s ( Unit ` L ) ) ) | 
						
							| 33 | 32 | oveqi |  |-  ( x ( .r ` L ) y ) = ( x ( +g ` ( ( mulGrp ` L ) |`s ( Unit ` L ) ) ) y ) | 
						
							| 34 | 19 26 33 | 3eqtr3g |  |-  ( ( ph /\ ( x e. ( Unit ` K ) /\ y e. ( Unit ` K ) ) ) -> ( x ( +g ` ( ( mulGrp ` K ) |`s ( Unit ` K ) ) ) y ) = ( x ( +g ` ( ( mulGrp ` L ) |`s ( Unit ` L ) ) ) y ) ) | 
						
							| 35 | 7 12 34 | grpinvpropd |  |-  ( ph -> ( invg ` ( ( mulGrp ` K ) |`s ( Unit ` K ) ) ) = ( invg ` ( ( mulGrp ` L ) |`s ( Unit ` L ) ) ) ) | 
						
							| 36 |  | eqid |  |-  ( invr ` K ) = ( invr ` K ) | 
						
							| 37 | 4 5 36 | invrfval |  |-  ( invr ` K ) = ( invg ` ( ( mulGrp ` K ) |`s ( Unit ` K ) ) ) | 
						
							| 38 |  | eqid |  |-  ( invr ` L ) = ( invr ` L ) | 
						
							| 39 | 9 10 38 | invrfval |  |-  ( invr ` L ) = ( invg ` ( ( mulGrp ` L ) |`s ( Unit ` L ) ) ) | 
						
							| 40 | 35 37 39 | 3eqtr4g |  |-  ( ph -> ( invr ` K ) = ( invr ` L ) ) |