Metamath Proof Explorer


Theorem lkrshp

Description: The kernel of a nonzero functional is a hyperplane. (Contributed by NM, 29-Jun-2014)

Ref Expression
Hypotheses lkrshp.v V = Base W
lkrshp.d D = Scalar W
lkrshp.z 0 ˙ = 0 D
lkrshp.h H = LSHyp W
lkrshp.f F = LFnl W
lkrshp.k K = LKer W
Assertion lkrshp W LVec G F G V × 0 ˙ K G H

Proof

Step Hyp Ref Expression
1 lkrshp.v V = Base W
2 lkrshp.d D = Scalar W
3 lkrshp.z 0 ˙ = 0 D
4 lkrshp.h H = LSHyp W
5 lkrshp.f F = LFnl W
6 lkrshp.k K = LKer W
7 lveclmod W LVec W LMod
8 7 3ad2ant1 W LVec G F G V × 0 ˙ W LMod
9 simp2 W LVec G F G V × 0 ˙ G F
10 eqid LSubSp W = LSubSp W
11 5 6 10 lkrlss W LMod G F K G LSubSp W
12 8 9 11 syl2anc W LVec G F G V × 0 ˙ K G LSubSp W
13 simp3 W LVec G F G V × 0 ˙ G V × 0 ˙
14 2 3 1 5 6 lkr0f W LMod G F K G = V G = V × 0 ˙
15 8 9 14 syl2anc W LVec G F G V × 0 ˙ K G = V G = V × 0 ˙
16 15 necon3bid W LVec G F G V × 0 ˙ K G V G V × 0 ˙
17 13 16 mpbird W LVec G F G V × 0 ˙ K G V
18 eqid 1 D = 1 D
19 2 3 18 1 5 lfl1 W LVec G F G V × 0 ˙ v V G v = 1 D
20 simp11 W LVec G F G V × 0 ˙ v V G v = 1 D W LVec
21 simp2 W LVec G F G V × 0 ˙ v V G v = 1 D v V
22 simp12 W LVec G F G V × 0 ˙ v V G v = 1 D G F
23 simp3 W LVec G F G V × 0 ˙ v V G v = 1 D G v = 1 D
24 2 lvecdrng W LVec D DivRing
25 3 18 drngunz D DivRing 1 D 0 ˙
26 20 24 25 3syl W LVec G F G V × 0 ˙ v V G v = 1 D 1 D 0 ˙
27 23 26 eqnetrd W LVec G F G V × 0 ˙ v V G v = 1 D G v 0 ˙
28 simpl11 W LVec G F G V × 0 ˙ v V G v = 1 D v K G W LVec
29 simpl12 W LVec G F G V × 0 ˙ v V G v = 1 D v K G G F
30 simpr W LVec G F G V × 0 ˙ v V G v = 1 D v K G v K G
31 2 3 5 6 lkrf0 W LVec G F v K G G v = 0 ˙
32 28 29 30 31 syl3anc W LVec G F G V × 0 ˙ v V G v = 1 D v K G G v = 0 ˙
33 32 ex W LVec G F G V × 0 ˙ v V G v = 1 D v K G G v = 0 ˙
34 33 necon3ad W LVec G F G V × 0 ˙ v V G v = 1 D G v 0 ˙ ¬ v K G
35 27 34 mpd W LVec G F G V × 0 ˙ v V G v = 1 D ¬ v K G
36 eqid LSpan W = LSpan W
37 1 36 5 6 lkrlsp3 W LVec v V G F ¬ v K G LSpan W K G v = V
38 20 21 22 35 37 syl121anc W LVec G F G V × 0 ˙ v V G v = 1 D LSpan W K G v = V
39 38 3expia W LVec G F G V × 0 ˙ v V G v = 1 D LSpan W K G v = V
40 39 reximdva W LVec G F G V × 0 ˙ v V G v = 1 D v V LSpan W K G v = V
41 19 40 mpd W LVec G F G V × 0 ˙ v V LSpan W K G v = V
42 1 36 10 4 islshp W LVec K G H K G LSubSp W K G V v V LSpan W K G v = V
43 42 3ad2ant1 W LVec G F G V × 0 ˙ K G H K G LSubSp W K G V v V LSpan W K G v = V
44 12 17 41 43 mpbir3and W LVec G F G V × 0 ˙ K G H