Metamath Proof Explorer


Theorem lsppr

Description: Span of a pair of vectors. (Contributed by NM, 22-Aug-2014)

Ref Expression
Hypotheses lsppr.v 𝑉 = ( Base ‘ 𝑊 )
lsppr.a + = ( +g𝑊 )
lsppr.f 𝐹 = ( Scalar ‘ 𝑊 )
lsppr.k 𝐾 = ( Base ‘ 𝐹 )
lsppr.t · = ( ·𝑠𝑊 )
lsppr.n 𝑁 = ( LSpan ‘ 𝑊 )
lsppr.w ( 𝜑𝑊 ∈ LMod )
lsppr.x ( 𝜑𝑋𝑉 )
lsppr.y ( 𝜑𝑌𝑉 )
Assertion lsppr ( 𝜑 → ( 𝑁 ‘ { 𝑋 , 𝑌 } ) = { 𝑣 ∣ ∃ 𝑘𝐾𝑙𝐾 𝑣 = ( ( 𝑘 · 𝑋 ) + ( 𝑙 · 𝑌 ) ) } )

Proof

Step Hyp Ref Expression
1 lsppr.v 𝑉 = ( Base ‘ 𝑊 )
2 lsppr.a + = ( +g𝑊 )
3 lsppr.f 𝐹 = ( Scalar ‘ 𝑊 )
4 lsppr.k 𝐾 = ( Base ‘ 𝐹 )
5 lsppr.t · = ( ·𝑠𝑊 )
6 lsppr.n 𝑁 = ( LSpan ‘ 𝑊 )
7 lsppr.w ( 𝜑𝑊 ∈ LMod )
8 lsppr.x ( 𝜑𝑋𝑉 )
9 lsppr.y ( 𝜑𝑌𝑉 )
10 df-pr { 𝑋 , 𝑌 } = ( { 𝑋 } ∪ { 𝑌 } )
11 10 fveq2i ( 𝑁 ‘ { 𝑋 , 𝑌 } ) = ( 𝑁 ‘ ( { 𝑋 } ∪ { 𝑌 } ) )
12 8 snssd ( 𝜑 → { 𝑋 } ⊆ 𝑉 )
13 9 snssd ( 𝜑 → { 𝑌 } ⊆ 𝑉 )
14 1 6 lspun ( ( 𝑊 ∈ LMod ∧ { 𝑋 } ⊆ 𝑉 ∧ { 𝑌 } ⊆ 𝑉 ) → ( 𝑁 ‘ ( { 𝑋 } ∪ { 𝑌 } ) ) = ( 𝑁 ‘ ( ( 𝑁 ‘ { 𝑋 } ) ∪ ( 𝑁 ‘ { 𝑌 } ) ) ) )
15 7 12 13 14 syl3anc ( 𝜑 → ( 𝑁 ‘ ( { 𝑋 } ∪ { 𝑌 } ) ) = ( 𝑁 ‘ ( ( 𝑁 ‘ { 𝑋 } ) ∪ ( 𝑁 ‘ { 𝑌 } ) ) ) )
16 eqid ( LSubSp ‘ 𝑊 ) = ( LSubSp ‘ 𝑊 )
17 1 16 6 lspsncl ( ( 𝑊 ∈ LMod ∧ 𝑋𝑉 ) → ( 𝑁 ‘ { 𝑋 } ) ∈ ( LSubSp ‘ 𝑊 ) )
18 7 8 17 syl2anc ( 𝜑 → ( 𝑁 ‘ { 𝑋 } ) ∈ ( LSubSp ‘ 𝑊 ) )
19 1 16 6 lspsncl ( ( 𝑊 ∈ LMod ∧ 𝑌𝑉 ) → ( 𝑁 ‘ { 𝑌 } ) ∈ ( LSubSp ‘ 𝑊 ) )
20 7 9 19 syl2anc ( 𝜑 → ( 𝑁 ‘ { 𝑌 } ) ∈ ( LSubSp ‘ 𝑊 ) )
21 eqid ( LSSum ‘ 𝑊 ) = ( LSSum ‘ 𝑊 )
22 16 6 21 lsmsp ( ( 𝑊 ∈ LMod ∧ ( 𝑁 ‘ { 𝑋 } ) ∈ ( LSubSp ‘ 𝑊 ) ∧ ( 𝑁 ‘ { 𝑌 } ) ∈ ( LSubSp ‘ 𝑊 ) ) → ( ( 𝑁 ‘ { 𝑋 } ) ( LSSum ‘ 𝑊 ) ( 𝑁 ‘ { 𝑌 } ) ) = ( 𝑁 ‘ ( ( 𝑁 ‘ { 𝑋 } ) ∪ ( 𝑁 ‘ { 𝑌 } ) ) ) )
23 7 18 20 22 syl3anc ( 𝜑 → ( ( 𝑁 ‘ { 𝑋 } ) ( LSSum ‘ 𝑊 ) ( 𝑁 ‘ { 𝑌 } ) ) = ( 𝑁 ‘ ( ( 𝑁 ‘ { 𝑋 } ) ∪ ( 𝑁 ‘ { 𝑌 } ) ) ) )
24 1 2 3 4 5 21 6 7 8 9 lsmspsn ( 𝜑 → ( 𝑣 ∈ ( ( 𝑁 ‘ { 𝑋 } ) ( LSSum ‘ 𝑊 ) ( 𝑁 ‘ { 𝑌 } ) ) ↔ ∃ 𝑘𝐾𝑙𝐾 𝑣 = ( ( 𝑘 · 𝑋 ) + ( 𝑙 · 𝑌 ) ) ) )
25 24 abbi2dv ( 𝜑 → ( ( 𝑁 ‘ { 𝑋 } ) ( LSSum ‘ 𝑊 ) ( 𝑁 ‘ { 𝑌 } ) ) = { 𝑣 ∣ ∃ 𝑘𝐾𝑙𝐾 𝑣 = ( ( 𝑘 · 𝑋 ) + ( 𝑙 · 𝑌 ) ) } )
26 15 23 25 3eqtr2d ( 𝜑 → ( 𝑁 ‘ ( { 𝑋 } ∪ { 𝑌 } ) ) = { 𝑣 ∣ ∃ 𝑘𝐾𝑙𝐾 𝑣 = ( ( 𝑘 · 𝑋 ) + ( 𝑙 · 𝑌 ) ) } )
27 11 26 eqtrid ( 𝜑 → ( 𝑁 ‘ { 𝑋 , 𝑌 } ) = { 𝑣 ∣ ∃ 𝑘𝐾𝑙𝐾 𝑣 = ( ( 𝑘 · 𝑋 ) + ( 𝑙 · 𝑌 ) ) } )