Question

For any two vectors a and b, find (a x b).b.

Answer 1

\((\vec a\times\vec b).\vec b=0\)

We know, \((\vec a\times\vec b)\) is perpendicular to both  \(\vec a\) and  \(\vec b\).

So, \((\vec a\times\vec b).\vec b=0\)

[\(\because\vec b\) and \((\vec a\times\vec b)\) are perpendicular to each other]