MCQ
With respect to a rectangular cartesian coordinate system, three vectors are expressed as
$\vec a = 4\hat i - \hat j$, $\vec b = - 3\hat i + 2\hat j$ and $\vec c = - \hat k$
where $\hat i,\,\hat j,\,\hat k$ are unit vectors, along the $X, Y $ and $Z-$axis respectively. The unit vectors $\hat r$ along the direction of sum of these vector is
- ✓$\hat r = \frac{1}{{\sqrt 3 }}(\hat i + \hat j - \hat k)$
- B$\hat r = \frac{1}{{\sqrt 2 }}(\hat i + \hat j - \hat k)$
- C$\hat r = \frac{1}{3}(\hat i - \hat j + \hat k)$
- D$\hat r = \frac{1}{{\sqrt 2 }}(\hat i + \hat j + \hat k)$
