1. The problem statement, all variables and given/known data Is it true in three dimensions that any two vectors perpendicular to a third one are parallel to each other? 2. Relevant equations Dot product. 3. The attempt at a solution I've come up with two vectors that were orthogonal to a third and found the angle between them using the definition of the dot product and the angle was not 180 degrees. Therefore I don't think that it's true. I'm really only here to check that I did my math right. Is it actually not true, or do I need to recalculate?