defence exam Army Havildar SAC Mock Test Series 2025 Mathematics Vector Algebra Scalar and Vector Product
If \(\vec{r} = \vec{a} \times (\vec{b}× \vec{c})+\vec{b}\times (\vec{c}\times \vec{a})+\vec{c}\times (\vec{a}\times \vec{b})\) then
1
\(\vec{r}\) is a unit vector
2
\(\vec{r} = \vec{0}\)
3
\(\vec{r}=\vec{a}+\vec{b}+\vec{c}\)
4
\(\vec{r}=\left(\vec{a}+\vec{b}+\vec{c}\right)^2\)