Metamath Proof Explorer

Theorem mendplusgfval

Description: Addition in the module endomorphism algebra. (Contributed by Stefan O'Rear, 2-Sep-2015) (Proof shortened by AV, 3-Mar-2024)

Ref Expression
Hypotheses mendplusgfval.a ⊢ 𝐴 = ( MEndo ‘ 𝑀 )
mendplusgfval.b ⊢ 𝐵 = ( Base ‘ 𝐴 )
mendplusgfval.p ⊢ + = ( +g ‘ 𝑀 )
Assertion mendplusgfval ( +g ‘ 𝐴 ) = ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) )

Proof

Step Hyp Ref Expression
1 mendplusgfval.a ⊢ 𝐴 = ( MEndo ‘ 𝑀 )
2 mendplusgfval.b ⊢ 𝐵 = ( Base ‘ 𝐴 )
3 mendplusgfval.p ⊢ + = ( +g ‘ 𝑀 )
4 1 mendbas ⊢ ( 𝑀 LMHom 𝑀 ) = ( Base ‘ 𝐴 )
5 2 4 eqtr4i ⊢ 𝐵 = ( 𝑀 LMHom 𝑀 )
6 ofeq ⊢ ( + = ( +g ‘ 𝑀 ) → ∘f + = ∘f ( +g ‘ 𝑀 ) )
7 3 6 ax-mp ⊢ ∘f + = ∘f ( +g ‘ 𝑀 )
8 7 oveqi ⊢ ( 𝑥 ∘f + 𝑦 ) = ( 𝑥 ∘f ( +g ‘ 𝑀 ) 𝑦 )
9 8 a1i ⊢ ( ( 𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵 ) → ( 𝑥 ∘f + 𝑦 ) = ( 𝑥 ∘f ( +g ‘ 𝑀 ) 𝑦 ) )
10 9 mpoeq3ia ⊢ ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) = ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f ( +g ‘ 𝑀 ) 𝑦 ) )
11 eqid ⊢ ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘ 𝑦 ) ) = ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘ 𝑦 ) )
12 eqid ⊢ ( Scalar ‘ 𝑀 ) = ( Scalar ‘ 𝑀 )
13 eqid ⊢ ( 𝑥 ∈ ( Base ‘ ( Scalar ‘ 𝑀 ) ) , 𝑦 ∈ 𝐵 ↦ ( ( ( Base ‘ 𝑀 ) × { 𝑥 } ) ∘f ( ·𝑠 ‘ 𝑀 ) 𝑦 ) ) = ( 𝑥 ∈ ( Base ‘ ( Scalar ‘ 𝑀 ) ) , 𝑦 ∈ 𝐵 ↦ ( ( ( Base ‘ 𝑀 ) × { 𝑥 } ) ∘f ( ·𝑠 ‘ 𝑀 ) 𝑦 ) )
14 5 10 11 12 13 mendval ⊢ ( 𝑀 ∈ V → ( MEndo ‘ 𝑀 ) = ( { ⟨ ( Base ‘ ndx ) , 𝐵 ⟩ , ⟨ ( +g ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) ⟩ , ⟨ ( .r ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘ 𝑦 ) ) ⟩ } ∪ { ⟨ ( Scalar ‘ ndx ) , ( Scalar ‘ 𝑀 ) ⟩ , ⟨ ( ·𝑠 ‘ ndx ) , ( 𝑥 ∈ ( Base ‘ ( Scalar ‘ 𝑀 ) ) , 𝑦 ∈ 𝐵 ↦ ( ( ( Base ‘ 𝑀 ) × { 𝑥 } ) ∘f ( ·𝑠 ‘ 𝑀 ) 𝑦 ) ) ⟩ } ) )
15 1 14 syl5eq ⊢ ( 𝑀 ∈ V → 𝐴 = ( { ⟨ ( Base ‘ ndx ) , 𝐵 ⟩ , ⟨ ( +g ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) ⟩ , ⟨ ( .r ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘ 𝑦 ) ) ⟩ } ∪ { ⟨ ( Scalar ‘ ndx ) , ( Scalar ‘ 𝑀 ) ⟩ , ⟨ ( ·𝑠 ‘ ndx ) , ( 𝑥 ∈ ( Base ‘ ( Scalar ‘ 𝑀 ) ) , 𝑦 ∈ 𝐵 ↦ ( ( ( Base ‘ 𝑀 ) × { 𝑥 } ) ∘f ( ·𝑠 ‘ 𝑀 ) 𝑦 ) ) ⟩ } ) )
16 15 fveq2d ⊢ ( 𝑀 ∈ V → ( +g ‘ 𝐴 ) = ( +g ‘ ( { ⟨ ( Base ‘ ndx ) , 𝐵 ⟩ , ⟨ ( +g ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) ⟩ , ⟨ ( .r ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘ 𝑦 ) ) ⟩ } ∪ { ⟨ ( Scalar ‘ ndx ) , ( Scalar ‘ 𝑀 ) ⟩ , ⟨ ( ·𝑠 ‘ ndx ) , ( 𝑥 ∈ ( Base ‘ ( Scalar ‘ 𝑀 ) ) , 𝑦 ∈ 𝐵 ↦ ( ( ( Base ‘ 𝑀 ) × { 𝑥 } ) ∘f ( ·𝑠 ‘ 𝑀 ) 𝑦 ) ) ⟩ } ) ) )
17 2 fvexi ⊢ 𝐵 ∈ V
18 17 17 mpoex ⊢ ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) ∈ V
19 eqid ⊢ ( { ⟨ ( Base ‘ ndx ) , 𝐵 ⟩ , ⟨ ( +g ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) ⟩ , ⟨ ( .r ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘ 𝑦 ) ) ⟩ } ∪ { ⟨ ( Scalar ‘ ndx ) , ( Scalar ‘ 𝑀 ) ⟩ , ⟨ ( ·𝑠 ‘ ndx ) , ( 𝑥 ∈ ( Base ‘ ( Scalar ‘ 𝑀 ) ) , 𝑦 ∈ 𝐵 ↦ ( ( ( Base ‘ 𝑀 ) × { 𝑥 } ) ∘f ( ·𝑠 ‘ 𝑀 ) 𝑦 ) ) ⟩ } ) = ( { ⟨ ( Base ‘ ndx ) , 𝐵 ⟩ , ⟨ ( +g ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) ⟩ , ⟨ ( .r ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘ 𝑦 ) ) ⟩ } ∪ { ⟨ ( Scalar ‘ ndx ) , ( Scalar ‘ 𝑀 ) ⟩ , ⟨ ( ·𝑠 ‘ ndx ) , ( 𝑥 ∈ ( Base ‘ ( Scalar ‘ 𝑀 ) ) , 𝑦 ∈ 𝐵 ↦ ( ( ( Base ‘ 𝑀 ) × { 𝑥 } ) ∘f ( ·𝑠 ‘ 𝑀 ) 𝑦 ) ) ⟩ } )
20 19 algaddg ⊢ ( ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) ∈ V → ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) = ( +g ‘ ( { ⟨ ( Base ‘ ndx ) , 𝐵 ⟩ , ⟨ ( +g ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) ⟩ , ⟨ ( .r ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘ 𝑦 ) ) ⟩ } ∪ { ⟨ ( Scalar ‘ ndx ) , ( Scalar ‘ 𝑀 ) ⟩ , ⟨ ( ·𝑠 ‘ ndx ) , ( 𝑥 ∈ ( Base ‘ ( Scalar ‘ 𝑀 ) ) , 𝑦 ∈ 𝐵 ↦ ( ( ( Base ‘ 𝑀 ) × { 𝑥 } ) ∘f ( ·𝑠 ‘ 𝑀 ) 𝑦 ) ) ⟩ } ) ) )
21 18 20 mp1i ⊢ ( 𝑀 ∈ V → ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) = ( +g ‘ ( { ⟨ ( Base ‘ ndx ) , 𝐵 ⟩ , ⟨ ( +g ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) ⟩ , ⟨ ( .r ‘ ndx ) , ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘ 𝑦 ) ) ⟩ } ∪ { ⟨ ( Scalar ‘ ndx ) , ( Scalar ‘ 𝑀 ) ⟩ , ⟨ ( ·𝑠 ‘ ndx ) , ( 𝑥 ∈ ( Base ‘ ( Scalar ‘ 𝑀 ) ) , 𝑦 ∈ 𝐵 ↦ ( ( ( Base ‘ 𝑀 ) × { 𝑥 } ) ∘f ( ·𝑠 ‘ 𝑀 ) 𝑦 ) ) ⟩ } ) ) )
22 16 21 eqtr4d ⊢ ( 𝑀 ∈ V → ( +g ‘ 𝐴 ) = ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) )
23 fvprc ⊢ ( ¬ 𝑀 ∈ V → ( MEndo ‘ 𝑀 ) = ∅ )
24 1 23 syl5eq ⊢ ( ¬ 𝑀 ∈ V → 𝐴 = ∅ )
25 24 fveq2d ⊢ ( ¬ 𝑀 ∈ V → ( +g ‘ 𝐴 ) = ( +g ‘ ∅ ) )
26 df-plusg ⊢ +g = Slot 2
27 26 str0 ⊢ ∅ = ( +g ‘ ∅ )
28 25 27 eqtr4di ⊢ ( ¬ 𝑀 ∈ V → ( +g ‘ 𝐴 ) = ∅ )
29 24 fveq2d ⊢ ( ¬ 𝑀 ∈ V → ( Base ‘ 𝐴 ) = ( Base ‘ ∅ ) )
30 base0 ⊢ ∅ = ( Base ‘ ∅ )
31 29 2 30 3eqtr4g ⊢ ( ¬ 𝑀 ∈ V → 𝐵 = ∅ )
32 31 olcd ⊢ ( ¬ 𝑀 ∈ V → ( 𝐵 = ∅ ∨ 𝐵 = ∅ ) )
33 0mpo0 ⊢ ( ( 𝐵 = ∅ ∨ 𝐵 = ∅ ) → ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) = ∅ )
34 32 33 syl ⊢ ( ¬ 𝑀 ∈ V → ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) = ∅ )
35 28 34 eqtr4d ⊢ ( ¬ 𝑀 ∈ V → ( +g ‘ 𝐴 ) = ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) ) )
36 22 35 pm2.61i ⊢ ( +g ‘ 𝐴 ) = ( 𝑥 ∈ 𝐵 , 𝑦 ∈ 𝐵 ↦ ( 𝑥 ∘f + 𝑦 ) )