Metamath Proof Explorer


Theorem dochfln0

Description: The value of a functional is nonzero at a nonzero vector in the orthocomplement of its kernel. (Contributed by NM, 2-Jan-2015)

Ref Expression
Hypotheses dochfln0.h ⊢ H = LHyp ⁡ K
dochfln0.o ⊢ ⊥ ˙ = ocH ⁡ K ⁡ W
dochfln0.u ⊢ U = DVecH ⁡ K ⁡ W
dochfln0.v ⊢ V = Base U
dochfln0.r ⊢ R = Scalar ⁡ U
dochfln0.n ⊢ N = 0 R
dochfln0.z ⊢ 0 ˙ = 0 U
dochfln0.f ⊢ F = LFnl ⁡ U
dochfln0.l ⊢ L = LKer ⁡ U
dochfln0.k ⊢ φ → K ∈ HL ∧ W ∈ H
dochfln0.g ⊢ φ → G ∈ F
dochfln0.x ⊢ φ → X ∈ ⊥ ˙ ⁡ L ⁡ G ∖ 0 ˙
Assertion dochfln0 ⊢ φ → G ⁡ X ≠ N

Proof

Step Hyp Ref Expression
1 dochfln0.h ⊢ H = LHyp ⁡ K
2 dochfln0.o ⊢ ⊥ ˙ = ocH ⁡ K ⁡ W
3 dochfln0.u ⊢ U = DVecH ⁡ K ⁡ W
4 dochfln0.v ⊢ V = Base U
5 dochfln0.r ⊢ R = Scalar ⁡ U
6 dochfln0.n ⊢ N = 0 R
7 dochfln0.z ⊢ 0 ˙ = 0 U
8 dochfln0.f ⊢ F = LFnl ⁡ U
9 dochfln0.l ⊢ L = LKer ⁡ U
10 dochfln0.k ⊢ φ → K ∈ HL ∧ W ∈ H
11 dochfln0.g ⊢ φ → G ∈ F
12 dochfln0.x ⊢ φ → X ∈ ⊥ ˙ ⁡ L ⁡ G ∖ 0 ˙
13 1 3 10 dvhlmod ⊢ φ → U ∈ LMod
14 4 8 9 13 11 lkrssv ⊢ φ → L ⁡ G ⊆ V
15 1 3 4 2 dochssv ⊢ K ∈ HL ∧ W ∈ H ∧ L ⁡ G ⊆ V → ⊥ ˙ ⁡ L ⁡ G ⊆ V
16 10 14 15 syl2anc ⊢ φ → ⊥ ˙ ⁡ L ⁡ G ⊆ V
17 16 ssdifd ⊢ φ → ⊥ ˙ ⁡ L ⁡ G ∖ 0 ˙ ⊆ V ∖ 0 ˙
18 17 12 sseldd ⊢ φ → X ∈ V ∖ 0 ˙
19 1 2 3 4 7 10 18 dochnel ⊢ φ → ¬ X ∈ ⊥ ˙ ⁡ X
20 12 eldifad ⊢ φ → X ∈ ⊥ ˙ ⁡ L ⁡ G
21 16 20 sseldd ⊢ φ → X ∈ V
22 21 biantrurd ⊢ φ → G ⁡ X = N ↔ X ∈ V ∧ G ⁡ X = N
23 4 5 6 8 9 ellkr ⊢ U ∈ LMod ∧ G ∈ F → X ∈ L ⁡ G ↔ X ∈ V ∧ G ⁡ X = N
24 13 11 23 syl2anc ⊢ φ → X ∈ L ⁡ G ↔ X ∈ V ∧ G ⁡ X = N
25 1 2 3 4 7 8 9 10 11 12 dochsnkr ⊢ φ → L ⁡ G = ⊥ ˙ ⁡ X
26 25 eleq2d ⊢ φ → X ∈ L ⁡ G ↔ X ∈ ⊥ ˙ ⁡ X
27 22 24 26 3bitr2rd ⊢ φ → X ∈ ⊥ ˙ ⁡ X ↔ G ⁡ X = N
28 27 necon3bbid ⊢ φ → ¬ X ∈ ⊥ ˙ ⁡ X ↔ G ⁡ X ≠ N
29 19 28 mpbid ⊢ φ → G ⁡ X ≠ N