Metamath Proof Explorer


Theorem hiassdi

Description: Distributive/associative law for inner product, useful for linearity proofs. (Contributed by NM, 10-May-2005) (New usage is discouraged.)

Ref Expression
Assertion hiassdi A B C D A B + C ih D = A B ih D + C ih D

Proof

Step Hyp Ref Expression
1 hvmulcl A B A B
2 ax-his2 A B C D A B + C ih D = A B ih D + C ih D
3 2 3expb A B C D A B + C ih D = A B ih D + C ih D
4 1 3 sylan A B C D A B + C ih D = A B ih D + C ih D
5 ax-his3 A B D A B ih D = A B ih D
6 5 3expa A B D A B ih D = A B ih D
7 6 adantrl A B C D A B ih D = A B ih D
8 7 oveq1d A B C D A B ih D + C ih D = A B ih D + C ih D
9 4 8 eqtrd A B C D A B + C ih D = A B ih D + C ih D