Metamath Proof Explorer


Theorem h1dei

Description: Membership in 1-dimensional subspace. (Contributed by NM, 7-Jul-2001) (Revised by Mario Carneiro, 15-May-2014) (New usage is discouraged.)

Ref Expression
Hypothesis h1deot.1 B
Assertion h1dei A B A x B ih x = 0 A ih x = 0

Proof

Step Hyp Ref Expression
1 h1deot.1 B
2 snssi B B
3 occl B B C
4 1 2 3 mp2b B C
5 4 chssii B
6 ocel B A B A x B A ih x = 0
7 5 6 ax-mp A B A x B A ih x = 0
8 1 h1deoi x B x x ih B = 0
9 orthcom x B x ih B = 0 B ih x = 0
10 1 9 mpan2 x x ih B = 0 B ih x = 0
11 10 pm5.32i x x ih B = 0 x B ih x = 0
12 8 11 bitri x B x B ih x = 0
13 12 imbi1i x B A ih x = 0 x B ih x = 0 A ih x = 0
14 impexp x B ih x = 0 A ih x = 0 x B ih x = 0 A ih x = 0
15 13 14 bitri x B A ih x = 0 x B ih x = 0 A ih x = 0
16 15 ralbii2 x B A ih x = 0 x B ih x = 0 A ih x = 0
17 16 anbi2i A x B A ih x = 0 A x B ih x = 0 A ih x = 0
18 7 17 bitri A B A x B ih x = 0 A ih x = 0