At what angle must the two forces $(x + y)$ and $(x -y)$ act so that the resultant may be $\sqrt {({x^2} + {y^2})} $
${\cos ^{ - 1}}\left( { - \frac{{{x^2} + {y^2}}}{{2({x^2} - {y^2})}}} \right)$
${\cos ^{ - 1}}\left( { - \frac{{2({x^2} - {y^2})}}{{{x^2} + {y^2}}}} \right)$
${\cos ^{ - 1}}\left( { - \frac{{{x^2} + {y^2}}}{{{x^2} - {y^2}}}} \right)$
${\cos ^{ - 1}}\left( { - \frac{{{x^2} - {y^2}}}{{{x^2} + {y^2}}}} \right)$
A vector $\vec A $ is rotated by a small angle $\Delta \theta$ radian $( \Delta \theta << 1)$ to get a new vector $\vec B$ In that case $\left| {\vec B - \vec A} \right|$ is
If the sum of two unit vectors is a unit vector, then magnitude of difference is
Magnitude of vector which comes on addition of two vectors, $6\hat i + 7\hat j$ and $3\hat i + 4\hat j$ is
Statement $I:$ If three forces $\vec{F}_{1}, \vec{F}_{2}$ and $\vec{F}_{3}$ are represented by three sides of a triangle and $\overrightarrow{{F}}_{1}+\overrightarrow{{F}}_{2}=-\overrightarrow{{F}}_{3}$, then these three forces are concurrent forces and satisfy the condition for equilibrium.
Statement $II:$ A triangle made up of three forces $\overrightarrow{{F}}_{1}, \overrightarrow{{F}}_{2}$ and $\overrightarrow{{F}}_{3}$ as its sides taken in the same order, satisfy the condition for translatory equilibrium.
In the light of the above statements, choose the most appropriate answer from the options given below:
Three vectors $\overrightarrow{\mathrm{OP}}, \overrightarrow{\mathrm{OQ}}$ and $\overrightarrow{\mathrm{OR}}$ each of magnitude $A$ are acting as shown in figure. The resultant of the three vectors is $A \sqrt{x}$. The value of $x$ is. . . . . . . . .