Metamath Proof Explorer


Theorem his52

Description: Associative law for inner product. (Contributed by NM, 13-Feb-2006) (New usage is discouraged.)

Ref Expression
Assertion his52 ABCBihAC=ABihC

Proof

Step Hyp Ref Expression
1 cjcl AA
2 his5 ABCBihAC=ABihC
3 1 2 syl3an1 ABCBihAC=ABihC
4 cjcj AA=A
5 4 oveq1d AABihC=ABihC
6 5 3ad2ant1 ABCABihC=ABihC
7 3 6 eqtrd ABCBihAC=ABihC