Metamath Proof Explorer


Theorem spanpr

Description: The span of a pair of vectors. (Contributed by NM, 9-Jun-2006) (New usage is discouraged.)

Ref Expression
Assertion spanpr ABspanA+BspanAB

Proof

Step Hyp Ref Expression
1 spansnsh AspanAS
2 spansnsh BspanBS
3 shscl spanASspanBSspanA+spanBS
4 1 2 3 syl2an ABspanA+spanBS
5 4 adantr ABxspanA+BspanA+spanBS
6 1 2 anim12i ABspanASspanBS
7 spansnid AAspanA
8 spansnid BBspanB
9 7 8 anim12i ABAspanABspanB
10 shsva spanASspanBSAspanABspanBA+BspanA+spanB
11 6 9 10 sylc ABA+BspanA+spanB
12 11 adantr ABxspanA+BA+BspanA+spanB
13 simpr ABxspanA+BxspanA+B
14 elspansn3 spanA+spanBSA+BspanA+spanBxspanA+BxspanA+spanB
15 5 12 13 14 syl3anc ABxspanA+BxspanA+spanB
16 15 ex ABxspanA+BxspanA+spanB
17 16 ssrdv ABspanA+BspanA+spanB
18 df-pr AB=AB
19 18 fveq2i spanAB=spanAB
20 snssi AA
21 snssi BB
22 spanun ABspanAB=spanA+spanB
23 20 21 22 syl2an ABspanAB=spanA+spanB
24 19 23 eqtr2id ABspanA+spanB=spanAB
25 17 24 sseqtrd ABspanA+BspanAB