Metamath Proof Explorer


Theorem lmicsym

Description: Module isomorphism is symmetric. (Contributed by Stefan O'Rear, 26-Feb-2015)

Ref Expression
Assertion lmicsym ( 𝑅𝑚 𝑆𝑆𝑚 𝑅 )

Proof

Step Hyp Ref Expression
1 brlmic ( 𝑅𝑚 𝑆 ↔ ( 𝑅 LMIso 𝑆 ) ≠ ∅ )
2 n0 ( ( 𝑅 LMIso 𝑆 ) ≠ ∅ ↔ ∃ 𝑓 𝑓 ∈ ( 𝑅 LMIso 𝑆 ) )
3 lmimcnv ( 𝑓 ∈ ( 𝑅 LMIso 𝑆 ) → 𝑓 ∈ ( 𝑆 LMIso 𝑅 ) )
4 brlmici ( 𝑓 ∈ ( 𝑆 LMIso 𝑅 ) → 𝑆𝑚 𝑅 )
5 3 4 syl ( 𝑓 ∈ ( 𝑅 LMIso 𝑆 ) → 𝑆𝑚 𝑅 )
6 5 exlimiv ( ∃ 𝑓 𝑓 ∈ ( 𝑅 LMIso 𝑆 ) → 𝑆𝑚 𝑅 )
7 2 6 sylbi ( ( 𝑅 LMIso 𝑆 ) ≠ ∅ → 𝑆𝑚 𝑅 )
8 1 7 sylbi ( 𝑅𝑚 𝑆𝑆𝑚 𝑅 )