Metamath Proof Explorer


Axiom ax-hvass

Description: Vector addition is associative. (Contributed by NM, 3-Sep-1999) (New usage is discouraged.)

Ref Expression
Assertion ax-hvass
|- ( ( A e. ~H /\ B e. ~H /\ C e. ~H ) -> ( ( A +h B ) +h C ) = ( A +h ( B +h C ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cA
 |-  A
1 chba
 |-  ~H
2 0 1 wcel
 |-  A e. ~H
3 cB
 |-  B
4 3 1 wcel
 |-  B e. ~H
5 cC
 |-  C
6 5 1 wcel
 |-  C e. ~H
7 2 4 6 w3a
 |-  ( A e. ~H /\ B e. ~H /\ C e. ~H )
8 cva
 |-  +h
9 0 3 8 co
 |-  ( A +h B )
10 9 5 8 co
 |-  ( ( A +h B ) +h C )
11 3 5 8 co
 |-  ( B +h C )
12 0 11 8 co
 |-  ( A +h ( B +h C ) )
13 10 12 wceq
 |-  ( ( A +h B ) +h C ) = ( A +h ( B +h C ) )
14 7 13 wi
 |-  ( ( A e. ~H /\ B e. ~H /\ C e. ~H ) -> ( ( A +h B ) +h C ) = ( A +h ( B +h C ) ) )