Metamath Proof Explorer


Theorem lmod1lem1

Description: Lemma 1 for lmod1 . (Contributed by AV, 28-Apr-2019)

Ref Expression
Hypothesis lmod1.m 𝑀 = ( { ⟨ ( Base ‘ ndx ) , { 𝐼 } ⟩ , ⟨ ( +g ‘ ndx ) , { ⟨ ⟨ 𝐼 , 𝐼 ⟩ , 𝐼 ⟩ } ⟩ , ⟨ ( Scalar ‘ ndx ) , 𝑅 ⟩ } ∪ { ⟨ ( ·𝑠 ‘ ndx ) , ( 𝑥 ∈ ( Base ‘ 𝑅 ) , 𝑦 ∈ { 𝐼 } ↦ 𝑦 ) ⟩ } )
Assertion lmod1lem1 ( ( 𝐼𝑉𝑅 ∈ Ring ∧ 𝑟 ∈ ( Base ‘ 𝑅 ) ) → ( 𝑟 ( ·𝑠𝑀 ) 𝐼 ) ∈ { 𝐼 } )

Proof

Step Hyp Ref Expression
1 lmod1.m 𝑀 = ( { ⟨ ( Base ‘ ndx ) , { 𝐼 } ⟩ , ⟨ ( +g ‘ ndx ) , { ⟨ ⟨ 𝐼 , 𝐼 ⟩ , 𝐼 ⟩ } ⟩ , ⟨ ( Scalar ‘ ndx ) , 𝑅 ⟩ } ∪ { ⟨ ( ·𝑠 ‘ ndx ) , ( 𝑥 ∈ ( Base ‘ 𝑅 ) , 𝑦 ∈ { 𝐼 } ↦ 𝑦 ) ⟩ } )
2 fvex ( Base ‘ 𝑅 ) ∈ V
3 snex { 𝐼 } ∈ V
4 3 a1i ( ( 𝐼𝑉𝑅 ∈ Ring ∧ 𝑟 ∈ ( Base ‘ 𝑅 ) ) → { 𝐼 } ∈ V )
5 mpoexga ( ( ( Base ‘ 𝑅 ) ∈ V ∧ { 𝐼 } ∈ V ) → ( 𝑥 ∈ ( Base ‘ 𝑅 ) , 𝑦 ∈ { 𝐼 } ↦ 𝑦 ) ∈ V )
6 2 4 5 sylancr ( ( 𝐼𝑉𝑅 ∈ Ring ∧ 𝑟 ∈ ( Base ‘ 𝑅 ) ) → ( 𝑥 ∈ ( Base ‘ 𝑅 ) , 𝑦 ∈ { 𝐼 } ↦ 𝑦 ) ∈ V )
7 1 lmodvsca ( ( 𝑥 ∈ ( Base ‘ 𝑅 ) , 𝑦 ∈ { 𝐼 } ↦ 𝑦 ) ∈ V → ( 𝑥 ∈ ( Base ‘ 𝑅 ) , 𝑦 ∈ { 𝐼 } ↦ 𝑦 ) = ( ·𝑠𝑀 ) )
8 6 7 syl ( ( 𝐼𝑉𝑅 ∈ Ring ∧ 𝑟 ∈ ( Base ‘ 𝑅 ) ) → ( 𝑥 ∈ ( Base ‘ 𝑅 ) , 𝑦 ∈ { 𝐼 } ↦ 𝑦 ) = ( ·𝑠𝑀 ) )
9 8 eqcomd ( ( 𝐼𝑉𝑅 ∈ Ring ∧ 𝑟 ∈ ( Base ‘ 𝑅 ) ) → ( ·𝑠𝑀 ) = ( 𝑥 ∈ ( Base ‘ 𝑅 ) , 𝑦 ∈ { 𝐼 } ↦ 𝑦 ) )
10 simprr ( ( ( 𝐼𝑉𝑅 ∈ Ring ∧ 𝑟 ∈ ( Base ‘ 𝑅 ) ) ∧ ( 𝑥 = 𝑟𝑦 = 𝐼 ) ) → 𝑦 = 𝐼 )
11 simp3 ( ( 𝐼𝑉𝑅 ∈ Ring ∧ 𝑟 ∈ ( Base ‘ 𝑅 ) ) → 𝑟 ∈ ( Base ‘ 𝑅 ) )
12 snidg ( 𝐼𝑉𝐼 ∈ { 𝐼 } )
13 12 3ad2ant1 ( ( 𝐼𝑉𝑅 ∈ Ring ∧ 𝑟 ∈ ( Base ‘ 𝑅 ) ) → 𝐼 ∈ { 𝐼 } )
14 9 10 11 13 13 ovmpod ( ( 𝐼𝑉𝑅 ∈ Ring ∧ 𝑟 ∈ ( Base ‘ 𝑅 ) ) → ( 𝑟 ( ·𝑠𝑀 ) 𝐼 ) = 𝐼 )
15 14 13 eqeltrd ( ( 𝐼𝑉𝑅 ∈ Ring ∧ 𝑟 ∈ ( Base ‘ 𝑅 ) ) → ( 𝑟 ( ·𝑠𝑀 ) 𝐼 ) ∈ { 𝐼 } )