Question

Given that \(\vec{a}\;.\;\vec{b} = 0\) and \(\vec{a}\;\times\;\vec{b} = \vec{0}\). when can you conclude about the vectors \(\vec{a} \;and \; \vec{b}\)

Answer 1

They can’t be parallel and perpendicular at the same time. 

∴ At least one of \(\vec{a} \;and \; \vec{b}\) is zero vector.