Metamath Proof Explorer


Theorem lindsun

Description: Condition for the union of two independent sets to be an independent set. (Contributed by Thierry Arnoux, 9-May-2023)

Ref Expression
Hypotheses lindsun.n N = LSpan W
lindsun.0 0 ˙ = 0 W
lindsun.w φ W LVec
lindsun.u φ U LIndS W
lindsun.v φ V LIndS W
lindsun.2 φ N U N V = 0 ˙
Assertion lindsun φ U V LIndS W

Proof

Step Hyp Ref Expression
1 lindsun.n N = LSpan W
2 lindsun.0 0 ˙ = 0 W
3 lindsun.w φ W LVec
4 lindsun.u φ U LIndS W
5 lindsun.v φ V LIndS W
6 lindsun.2 φ N U N V = 0 ˙
7 lveclmod W LVec W LMod
8 3 7 syl φ W LMod
9 eqid Base W = Base W
10 9 linds1 U LIndS W U Base W
11 4 10 syl φ U Base W
12 9 linds1 V LIndS W V Base W
13 5 12 syl φ V Base W
14 11 13 unssd φ U V Base W
15 3 ad3antrrr φ k Base Scalar W 0 Scalar W k W c N U V c c U W LVec
16 4 ad3antrrr φ k Base Scalar W 0 Scalar W k W c N U V c c U U LIndS W
17 5 ad3antrrr φ k Base Scalar W 0 Scalar W k W c N U V c c U V LIndS W
18 6 ad3antrrr φ k Base Scalar W 0 Scalar W k W c N U V c c U N U N V = 0 ˙
19 eqid 0 Scalar W = 0 Scalar W
20 eqid Base Scalar W = Base Scalar W
21 simpr φ k Base Scalar W 0 Scalar W k W c N U V c c U c U
22 simpllr φ k Base Scalar W 0 Scalar W k W c N U V c c U k Base Scalar W 0 Scalar W
23 simplr φ k Base Scalar W 0 Scalar W k W c N U V c c U k W c N U V c
24 1 2 15 16 17 18 19 20 21 22 23 lindsunlem φ k Base Scalar W 0 Scalar W k W c N U V c c U
25 24 adantlr φ k Base Scalar W 0 Scalar W k W c N U V c c U V c U
26 3 ad3antrrr φ k Base Scalar W 0 Scalar W k W c N U V c c V W LVec
27 5 ad3antrrr φ k Base Scalar W 0 Scalar W k W c N U V c c V V LIndS W
28 4 ad3antrrr φ k Base Scalar W 0 Scalar W k W c N U V c c V U LIndS W
29 incom N U N V = N V N U
30 29 6 eqtr3id φ N V N U = 0 ˙
31 30 ad3antrrr φ k Base Scalar W 0 Scalar W k W c N U V c c V N V N U = 0 ˙
32 simpr φ k Base Scalar W 0 Scalar W k W c N U V c c V c V
33 simpllr φ k Base Scalar W 0 Scalar W k W c N U V c c V k Base Scalar W 0 Scalar W
34 simplr φ k Base Scalar W 0 Scalar W k W c N U V c c V k W c N U V c
35 uncom U V = V U
36 35 difeq1i U V c = V U c
37 36 fveq2i N U V c = N V U c
38 34 37 eleqtrdi φ k Base Scalar W 0 Scalar W k W c N U V c c V k W c N V U c
39 1 2 26 27 28 31 19 20 32 33 38 lindsunlem φ k Base Scalar W 0 Scalar W k W c N U V c c V
40 39 adantlr φ k Base Scalar W 0 Scalar W k W c N U V c c U V c V
41 elun c U V c U c V
42 41 biimpi c U V c U c V
43 42 adantl φ k Base Scalar W 0 Scalar W k W c N U V c c U V c U c V
44 25 40 43 mpjaodan φ k Base Scalar W 0 Scalar W k W c N U V c c U V
45 44 an32s φ k Base Scalar W 0 Scalar W c U V k W c N U V c
46 45 inegd φ k Base Scalar W 0 Scalar W c U V ¬ k W c N U V c
47 46 an32s φ c U V k Base Scalar W 0 Scalar W ¬ k W c N U V c
48 47 anasss φ c U V k Base Scalar W 0 Scalar W ¬ k W c N U V c
49 48 ralrimivva φ c U V k Base Scalar W 0 Scalar W ¬ k W c N U V c
50 eqid W = W
51 eqid Scalar W = Scalar W
52 9 50 1 51 20 19 islinds2 W LMod U V LIndS W U V Base W c U V k Base Scalar W 0 Scalar W ¬ k W c N U V c
53 52 biimpar W LMod U V Base W c U V k Base Scalar W 0 Scalar W ¬ k W c N U V c U V LIndS W
54 8 14 49 53 syl12anc φ U V LIndS W