1. The problem statement, all variables and given/known data If theta is the angle between two non-zero vectors A and B, then which of the following angles theta results in A dot B = |A x B|? 2. Relevant equations A dot B = ABcos(theta) A x B = ABsin(theta) 3. The attempt at a solution There were two choices in the multiple choice answers where cos(theta) = |sin(theta)| 1 is 225 degrees and the other is 315 degrees. The correct answer is 315 degrees. Can somebody explain or help illustrate why 225 is wrong and 315 is right?