Proving perpendicular vectors using Dot Product

[crayzwalz]

Homework Statement

Homework Equations

dot product a.b = lal.lblcostheta
vectors are perpendicular when a.b = 0

The Attempt at a Solution

OA . LA = 0
OA = OM + MA
LA = LO + OA

OA . LA = (OM+MA) . (LO + OA)
= OM.LO + OM.OA + MA.LO + MA.OAi get stuck here

 

[LCKurtz]

Look at this image and try this, the notation is a little easier.

See if you can show A = (1/2)(S-R) and V = (1/2)(S+R)

Once you do that see if you can show A dot B = 0.