Metamath Proof Explorer


Theorem lindszr

Description: Any subset of a module over a zero ring is always linearly independent. (Contributed by AV, 27-Apr-2019)

Ref Expression
Assertion lindszr ( ( 𝑀 ∈ LMod ∧ ¬ ( Scalar ‘ 𝑀 ) ∈ NzRing ∧ 𝑆 ∈ 𝒫 ( Base ‘ 𝑀 ) ) → 𝑆 linIndS 𝑀 )

Proof

Step Hyp Ref Expression
1 simp2 ( ( 𝑀 ∈ LMod ∧ ¬ ( Scalar ‘ 𝑀 ) ∈ NzRing ∧ 𝑆 ∈ 𝒫 ( Base ‘ 𝑀 ) ) → ¬ ( Scalar ‘ 𝑀 ) ∈ NzRing )
2 eqid ( Scalar ‘ 𝑀 ) = ( Scalar ‘ 𝑀 )
3 2 lmodring ( 𝑀 ∈ LMod → ( Scalar ‘ 𝑀 ) ∈ Ring )
4 3 3ad2ant1 ( ( 𝑀 ∈ LMod ∧ ¬ ( Scalar ‘ 𝑀 ) ∈ NzRing ∧ 𝑆 ∈ 𝒫 ( Base ‘ 𝑀 ) ) → ( Scalar ‘ 𝑀 ) ∈ Ring )
5 0ringnnzr ( ( Scalar ‘ 𝑀 ) ∈ Ring → ( ( ♯ ‘ ( Base ‘ ( Scalar ‘ 𝑀 ) ) ) = 1 ↔ ¬ ( Scalar ‘ 𝑀 ) ∈ NzRing ) )
6 4 5 syl ( ( 𝑀 ∈ LMod ∧ ¬ ( Scalar ‘ 𝑀 ) ∈ NzRing ∧ 𝑆 ∈ 𝒫 ( Base ‘ 𝑀 ) ) → ( ( ♯ ‘ ( Base ‘ ( Scalar ‘ 𝑀 ) ) ) = 1 ↔ ¬ ( Scalar ‘ 𝑀 ) ∈ NzRing ) )
7 1 6 mpbird ( ( 𝑀 ∈ LMod ∧ ¬ ( Scalar ‘ 𝑀 ) ∈ NzRing ∧ 𝑆 ∈ 𝒫 ( Base ‘ 𝑀 ) ) → ( ♯ ‘ ( Base ‘ ( Scalar ‘ 𝑀 ) ) ) = 1 )
8 7 olcd ( ( 𝑀 ∈ LMod ∧ ¬ ( Scalar ‘ 𝑀 ) ∈ NzRing ∧ 𝑆 ∈ 𝒫 ( Base ‘ 𝑀 ) ) → ( ( ♯ ‘ ( Base ‘ ( Scalar ‘ 𝑀 ) ) ) = 0 ∨ ( ♯ ‘ ( Base ‘ ( Scalar ‘ 𝑀 ) ) ) = 1 ) )
9 eqid ( Base ‘ 𝑀 ) = ( Base ‘ 𝑀 )
10 eqid ( Base ‘ ( Scalar ‘ 𝑀 ) ) = ( Base ‘ ( Scalar ‘ 𝑀 ) )
11 9 2 10 lindsrng01 ( ( 𝑀 ∈ LMod ∧ ( ( ♯ ‘ ( Base ‘ ( Scalar ‘ 𝑀 ) ) ) = 0 ∨ ( ♯ ‘ ( Base ‘ ( Scalar ‘ 𝑀 ) ) ) = 1 ) ∧ 𝑆 ∈ 𝒫 ( Base ‘ 𝑀 ) ) → 𝑆 linIndS 𝑀 )
12 8 11 syld3an2 ( ( 𝑀 ∈ LMod ∧ ¬ ( Scalar ‘ 𝑀 ) ∈ NzRing ∧ 𝑆 ∈ 𝒫 ( Base ‘ 𝑀 ) ) → 𝑆 linIndS 𝑀 )