Description: Every free module is isomorphic to the free module of "column vectors" of the same dimension over the same (nonzero) ring. (Contributed by AV, 10-Mar-2019)
Ref | Expression | ||
---|---|---|---|
Assertion | frlmiscvec | ⊢ ( ( 𝑅 ∈ NzRing ∧ 𝐼 ∈ 𝑌 ) → ( 𝑅 freeLMod 𝐼 ) ≃𝑚 ( 𝑅 freeLMod ( 𝐼 × { ∅ } ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | simpr | ⊢ ( ( 𝑅 ∈ NzRing ∧ 𝐼 ∈ 𝑌 ) → 𝐼 ∈ 𝑌 ) | |
2 | 0ex | ⊢ ∅ ∈ V | |
3 | xpsneng | ⊢ ( ( 𝐼 ∈ 𝑌 ∧ ∅ ∈ V ) → ( 𝐼 × { ∅ } ) ≈ 𝐼 ) | |
4 | 3 | ensymd | ⊢ ( ( 𝐼 ∈ 𝑌 ∧ ∅ ∈ V ) → 𝐼 ≈ ( 𝐼 × { ∅ } ) ) |
5 | 1 2 4 | sylancl | ⊢ ( ( 𝑅 ∈ NzRing ∧ 𝐼 ∈ 𝑌 ) → 𝐼 ≈ ( 𝐼 × { ∅ } ) ) |
6 | frlmisfrlm | ⊢ ( ( 𝑅 ∈ NzRing ∧ 𝐼 ∈ 𝑌 ∧ 𝐼 ≈ ( 𝐼 × { ∅ } ) ) → ( 𝑅 freeLMod 𝐼 ) ≃𝑚 ( 𝑅 freeLMod ( 𝐼 × { ∅ } ) ) ) | |
7 | 5 6 | mpd3an3 | ⊢ ( ( 𝑅 ∈ NzRing ∧ 𝐼 ∈ 𝑌 ) → ( 𝑅 freeLMod 𝐼 ) ≃𝑚 ( 𝑅 freeLMod ( 𝐼 × { ∅ } ) ) ) |