Metamath Proof Explorer


Theorem h1de2ci

Description: Membership in 1-dimensional subspace. All members are collinear with the generating vector. (Contributed by NM, 21-Jul-2001) (Revised by Mario Carneiro, 15-May-2014) (New usage is discouraged.)

Ref Expression
Hypothesis h1de2ct.1 B
Assertion h1de2ci ABxA=xB

Proof

Step Hyp Ref Expression
1 h1de2ct.1 B
2 snssi BB
3 occl BBC
4 1 2 3 mp2b BC
5 4 choccli BC
6 5 cheli ABA
7 hvmulcl xBxB
8 1 7 mpan2 xxB
9 eleq1 A=xBAxB
10 8 9 syl5ibrcom xA=xBA
11 10 rexlimiv xA=xBA
12 eleq1 A=ifAA0ABifAA0B
13 eqeq1 A=ifAA0A=xBifAA0=xB
14 13 rexbidv A=ifAA0xA=xBxifAA0=xB
15 12 14 bibi12d A=ifAA0ABxA=xBifAA0BxifAA0=xB
16 ifhvhv0 ifAA0
17 16 1 h1de2ctlem ifAA0BxifAA0=xB
18 15 17 dedth AABxA=xB
19 6 11 18 pm5.21nii ABxA=xB