Question
Let the vectors $\vec a\;$ and $\vec b$ be such that $\left| {\vec a} \right| = 3\;$ and $\;\left| b \right| = \frac{{\sqrt 2 }}{3},\;$ then $\;\vec a \times \vec b$ is a unit vector if the angle between $\vec a\;$ and $\vec b\;$ is

Answer

It is given that $\overrightarrow{a}\times \overrightarrow{b}$ is a unit vector, then:
$\Rightarrow |\vec a\times \vec b|=1\Rightarrow |\vec a||\vec b|sin\theta =1$
$\Rightarrow 3.\frac{\sqrt2}{3}sin\theta=1\Rightarrow sin\theta =\frac{1}{\sqrt2}\Rightarrow \theta =\frac{\pi}{4}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free