Question
Assertion : If $\theta$ be the angle between $\vec{A}$ and $\vec{B}$, then
$
\tan \theta=\frac{\vec{A} \times \vec{B}}{\vec{A} \cdot \vec{B}}
$
Reason $\quad: \quad \vec{A} \times \vec{B}$ is perpendicular to $\vec{A} \cdot \vec{B}$
$
\tan \theta=\frac{\vec{A} \times \vec{B}}{\vec{A} \cdot \vec{B}}
$
Reason $\quad: \quad \vec{A} \times \vec{B}$ is perpendicular to $\vec{A} \cdot \vec{B}$