Two vectors $\vec A$ and $\vec B$ have equal magnitudes. The magnitude of $(\vec A + \vec B)$ is $‘n’$ times the magnitude of $(\vec A - \vec B)$. The angle between $ \vec A$ and $\vec B$ is
${\cos ^{ - 1}}\left[ {\frac{{{n^2} - 1}}{{{n^2} + 1}}} \right]$
${\cos ^{ - 1}}\left[ {\frac{{n - 1}}{{n + 1}}} \right]$
${\sin ^{ - 1}}\left[ {\frac{{{n^2} - 1}}{{{n^2} + 1}}} \right]$
${\sin ^{ - 1}}\left[ {\frac{{n - 1}}{{n + 1}}} \right]$
Given that $\overrightarrow A + \overrightarrow B + \overrightarrow C= 0$ out of three vectors two are equal in magnitude and the magnitude of third vector is $\sqrt 2 $ times that of either of the two having equal magnitude. Then the angles between vectors are given by
Five equal forces of $10 \,N$ each are applied at one point and all are lying in one plane. If the angles between them are equal, the resultant force will be ........... $\mathrm{N}$
What is the meaning of substraction of two vectors ?
The resultant force of $5 \,N$ and $10 \,N$ can not be ........ $N$