Metamath Proof Explorer


Theorem frlmbasfn

Description: Elements of the free module are functions. (They map an index to the coordinate at that index, see frlmbasf ). (Contributed by SN, 23-Sep-2026)

Ref Expression
Hypotheses frlmbasfn.f ⊢ 𝐹 = ( 𝑅 freeLMod 𝐼 )
frlmbasfn.b ⊢ 𝐵 = ( Base ‘ 𝐹 )
frlmbasfn.i ⊢ ( 𝜑 → 𝐼 ∈ 𝑊 )
frlmbasfn.x ⊢ ( 𝜑 → 𝑋 ∈ 𝐵 )
Assertion frlmbasfn ( 𝜑 → 𝑋 Fn 𝐼 )

Proof

Step Hyp Ref Expression
1 frlmbasfn.f ⊢ 𝐹 = ( 𝑅 freeLMod 𝐼 )
2 frlmbasfn.b ⊢ 𝐵 = ( Base ‘ 𝐹 )
3 frlmbasfn.i ⊢ ( 𝜑 → 𝐼 ∈ 𝑊 )
4 frlmbasfn.x ⊢ ( 𝜑 → 𝑋 ∈ 𝐵 )
5 eqid ⊢ ( Base ‘ 𝑅 ) = ( Base ‘ 𝑅 )
6 1 5 2 frlmbasf ⊢ ( ( 𝐼 ∈ 𝑊 ∧ 𝑋 ∈ 𝐵 ) → 𝑋 : 𝐼 ⟶ ( Base ‘ 𝑅 ) )
7 3 4 6 syl2anc ⊢ ( 𝜑 → 𝑋 : 𝐼 ⟶ ( Base ‘ 𝑅 ) )
8 7 ffnd ⊢ ( 𝜑 → 𝑋 Fn 𝐼 )