Let $\bar{a} = \bar{i} + 2\bar{j} + 3\bar{k}$,$\bar{b} = 2\bar{i} - 3\bar{j} + \bar{k}$,and $\bar{c} = 3\bar{i} + \bar{j} - 2\bar{k}$ be three vectors. If $\bar{r}$ is a vector such that $\bar{r} \cdot \bar{a} = 0$,$\bar{r} \cdot \bar{b} = -2$,and $\bar{r} \cdot \bar{c} = 6$,then find the value of $\bar{r} \cdot (3\bar{i} + \bar{j} + \bar{k})$.

The angle between the diagonals of the parallelogram whose adjacent sides are $2 \hat{i}+4 \hat{j}-5 \hat{k}$ and $\hat{i}+2 \hat{j}+3 \hat{k}$ is

Let $O$ be the origin and $PQR$ be an arbitrary triangle. If a point $S$ satisfies the condition $\overrightarrow{OP} \cdot \overrightarrow{OQ} + \overrightarrow{OR} \cdot \overrightarrow{OS} = \overrightarrow{OR} \cdot \overrightarrow{OP} + \overrightarrow{OQ} \cdot \overrightarrow{OS} = \overrightarrow{OQ} \cdot \overrightarrow{OR} + \overrightarrow{OP} \cdot \overrightarrow{OS}$,then the point $S$ is the:

Let $\overrightarrow{a}=\hat{i}+\alpha \hat{j}+\beta \hat{k}$,where $\alpha, \beta \in R$. Let a vector $\overrightarrow{b}$ be such that the angle between $\vec{a}$ and $\vec{b}$ is $\frac{\pi}{4}$ and $|\vec{b}|^2=6$. If $\vec{a} \cdot \vec{b}=3 \sqrt{2}$,then the value of $(\alpha^2+\beta^2)|\vec{a} \times \vec{b}|^2$ is equal to

If $\vec{a}, \vec{b}, \text{ and } \vec{c}$ are non-coplanar vectors,then the point of intersection of the line passing through the points $2 \vec{a}+3 \vec{b}-\vec{c}$ and $3 \vec{a}+4 \vec{b}-2 \vec{c}$ with the line joining the points $\vec{a}-2 \vec{b}+3 \vec{c}$ and $\vec{a}-6 \vec{b}+6 \vec{c}$ is

Let $\overline{A}=2 \hat{i}+\hat{k}$,$\overline{B}=\hat{i}+\hat{j}+\hat{k}$ and $\overline{C}=4 \hat{i}-3 \hat{j}+7 \hat{k}$. If a vector $\overline{R}$ satisfies $\overline{R} \times \overline{B}=\overline{C} \times \overline{B}$ and $\overline{R} \cdot \overline{A}=0$,then $\overline{R}$ is given by