Metamath Proof Explorer


Theorem dochspss

Description: The span of a set of vectors is included in their double orthocomplement. (Contributed by NM, 26-Jul-2014)

Ref Expression
Hypotheses dochsp.h H = LHyp K
dochsp.u U = DVecH K W
dochsp.o ˙ = ocH K W
dochsp.v V = Base U
dochsp.n N = LSpan U
dochsp.k φ K HL W H
dochsp.x φ X V
Assertion dochspss φ N X ˙ ˙ X

Proof

Step Hyp Ref Expression
1 dochsp.h H = LHyp K
2 dochsp.u U = DVecH K W
3 dochsp.o ˙ = ocH K W
4 dochsp.v V = Base U
5 dochsp.n N = LSpan U
6 dochsp.k φ K HL W H
7 dochsp.x φ X V
8 eqid DIsoH K W = DIsoH K W
9 eqid LSubSp U = LSubSp U
10 1 2 8 9 dihsslss K HL W H ran DIsoH K W LSubSp U
11 rabss2 ran DIsoH K W LSubSp U z ran DIsoH K W | X z z LSubSp U | X z
12 intss z ran DIsoH K W | X z z LSubSp U | X z z LSubSp U | X z z ran DIsoH K W | X z
13 6 10 11 12 4syl φ z LSubSp U | X z z ran DIsoH K W | X z
14 1 2 6 dvhlmod φ U LMod
15 4 9 5 lspval U LMod X V N X = z LSubSp U | X z
16 14 7 15 syl2anc φ N X = z LSubSp U | X z
17 1 8 2 4 3 6 7 doch2val2 φ ˙ ˙ X = z ran DIsoH K W | X z
18 13 16 17 3sstr4d φ N X ˙ ˙ X