| Step | Hyp | Ref | Expression | 
						
							| 1 |  | coe1add.y |  |-  Y = ( Poly1 ` R ) | 
						
							| 2 |  | coe1add.b |  |-  B = ( Base ` Y ) | 
						
							| 3 |  | coe1add.p |  |-  .+b = ( +g ` Y ) | 
						
							| 4 |  | coe1add.q |  |-  .+ = ( +g ` R ) | 
						
							| 5 |  | eqid |  |-  ( 1o mPoly R ) = ( 1o mPoly R ) | 
						
							| 6 | 1 2 | ply1bas |  |-  B = ( Base ` ( 1o mPoly R ) ) | 
						
							| 7 | 1 5 3 | ply1plusg |  |-  .+b = ( +g ` ( 1o mPoly R ) ) | 
						
							| 8 |  | simp2 |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> F e. B ) | 
						
							| 9 |  | simp3 |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> G e. B ) | 
						
							| 10 | 5 6 4 7 8 9 | mpladd |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( F .+b G ) = ( F oF .+ G ) ) | 
						
							| 11 | 10 | coeq1d |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( ( F .+b G ) o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) = ( ( F oF .+ G ) o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) ) | 
						
							| 12 |  | eqid |  |-  ( Base ` R ) = ( Base ` R ) | 
						
							| 13 | 1 2 12 | ply1basf |  |-  ( F e. B -> F : ( NN0 ^m 1o ) --> ( Base ` R ) ) | 
						
							| 14 | 13 | ffnd |  |-  ( F e. B -> F Fn ( NN0 ^m 1o ) ) | 
						
							| 15 | 14 | 3ad2ant2 |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> F Fn ( NN0 ^m 1o ) ) | 
						
							| 16 | 1 2 12 | ply1basf |  |-  ( G e. B -> G : ( NN0 ^m 1o ) --> ( Base ` R ) ) | 
						
							| 17 | 16 | ffnd |  |-  ( G e. B -> G Fn ( NN0 ^m 1o ) ) | 
						
							| 18 | 17 | 3ad2ant3 |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> G Fn ( NN0 ^m 1o ) ) | 
						
							| 19 |  | df1o2 |  |-  1o = { (/) } | 
						
							| 20 |  | nn0ex |  |-  NN0 e. _V | 
						
							| 21 |  | 0ex |  |-  (/) e. _V | 
						
							| 22 |  | eqid |  |-  ( a e. NN0 |-> ( 1o X. { a } ) ) = ( a e. NN0 |-> ( 1o X. { a } ) ) | 
						
							| 23 | 19 20 21 22 | mapsnf1o3 |  |-  ( a e. NN0 |-> ( 1o X. { a } ) ) : NN0 -1-1-onto-> ( NN0 ^m 1o ) | 
						
							| 24 |  | f1of |  |-  ( ( a e. NN0 |-> ( 1o X. { a } ) ) : NN0 -1-1-onto-> ( NN0 ^m 1o ) -> ( a e. NN0 |-> ( 1o X. { a } ) ) : NN0 --> ( NN0 ^m 1o ) ) | 
						
							| 25 | 23 24 | mp1i |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( a e. NN0 |-> ( 1o X. { a } ) ) : NN0 --> ( NN0 ^m 1o ) ) | 
						
							| 26 |  | ovexd |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( NN0 ^m 1o ) e. _V ) | 
						
							| 27 | 20 | a1i |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> NN0 e. _V ) | 
						
							| 28 |  | inidm |  |-  ( ( NN0 ^m 1o ) i^i ( NN0 ^m 1o ) ) = ( NN0 ^m 1o ) | 
						
							| 29 | 15 18 25 26 26 27 28 | ofco |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( ( F oF .+ G ) o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) = ( ( F o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) oF .+ ( G o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) ) ) | 
						
							| 30 | 11 29 | eqtrd |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( ( F .+b G ) o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) = ( ( F o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) oF .+ ( G o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) ) ) | 
						
							| 31 | 1 | ply1ring |  |-  ( R e. Ring -> Y e. Ring ) | 
						
							| 32 | 2 3 | ringacl |  |-  ( ( Y e. Ring /\ F e. B /\ G e. B ) -> ( F .+b G ) e. B ) | 
						
							| 33 | 31 32 | syl3an1 |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( F .+b G ) e. B ) | 
						
							| 34 |  | eqid |  |-  ( coe1 ` ( F .+b G ) ) = ( coe1 ` ( F .+b G ) ) | 
						
							| 35 | 34 2 1 22 | coe1fval2 |  |-  ( ( F .+b G ) e. B -> ( coe1 ` ( F .+b G ) ) = ( ( F .+b G ) o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) ) | 
						
							| 36 | 33 35 | syl |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( coe1 ` ( F .+b G ) ) = ( ( F .+b G ) o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) ) | 
						
							| 37 |  | eqid |  |-  ( coe1 ` F ) = ( coe1 ` F ) | 
						
							| 38 | 37 2 1 22 | coe1fval2 |  |-  ( F e. B -> ( coe1 ` F ) = ( F o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) ) | 
						
							| 39 | 38 | 3ad2ant2 |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( coe1 ` F ) = ( F o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) ) | 
						
							| 40 |  | eqid |  |-  ( coe1 ` G ) = ( coe1 ` G ) | 
						
							| 41 | 40 2 1 22 | coe1fval2 |  |-  ( G e. B -> ( coe1 ` G ) = ( G o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) ) | 
						
							| 42 | 41 | 3ad2ant3 |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( coe1 ` G ) = ( G o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) ) | 
						
							| 43 | 39 42 | oveq12d |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( ( coe1 ` F ) oF .+ ( coe1 ` G ) ) = ( ( F o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) oF .+ ( G o. ( a e. NN0 |-> ( 1o X. { a } ) ) ) ) ) | 
						
							| 44 | 30 36 43 | 3eqtr4d |  |-  ( ( R e. Ring /\ F e. B /\ G e. B ) -> ( coe1 ` ( F .+b G ) ) = ( ( coe1 ` F ) oF .+ ( coe1 ` G ) ) ) |