Question

Two vectors have magnitude $2m$ and $3m$. The angle between them is ${60}^o$.Find
(a) The scalar product of the two vectors.
(b) The magnitude of their vector products.

Answer 1

$\left(a\right)$

$\overrightarrow{A}.\overrightarrow{B}=AB\cos {60}^o=2\times 3\times \frac{1}{2}=3$

$\left(b\right)$

$\overrightarrow{A}\times \overrightarrow{B}=AB\sin {60}^o=2\times 3\times \frac{\sqrt{3}}{2}=3\sqrt{3}$