The value of $\left| {\,\begin{array}{*{20}{c}}1&{\cos (\beta - \alpha )}&{\cos (\gamma - \alpha )}\\{\cos (\alpha - \beta )}&1&{\cos (\gamma - \beta )}\\{\cos (\alpha - \gamma )}&{\cos (\beta - \gamma )}&1\end{array}} \right|$ is
${\left| {\,\begin{array}{*{20}{c}}{\cos \alpha }&{\sin \alpha }&1\\{\cos \beta }&{\sin \beta }&1\\{\cos \gamma }&{\sin \gamma }&1\end{array}\,} \right|^2}$
${\left| {\,\begin{array}{*{20}{c}}{\sin \alpha }&{\cos \alpha }&0\\{\sin \beta }&{\cos \beta }&0\\{\sin \gamma }&{\cos \gamma }&0\end{array}\,} \right|^2}$
${\left| {\,\begin{array}{*{20}{c}}{\cos \alpha }&{\sin \alpha }&0\\{\sin \beta }&0&{\cos \beta }\\0&{\cos \gamma }&{\sin \gamma }\end{array}\,} \right|^2}$
None of these
Let $N$ denote the number that turns up when a fair die is rolled. If the probability that the system of equations
$x+y+z=1$ ; $2 x+N y+2 z=2$ ; $3 x+3 y+N z=3$
has unique solution is $\frac{k}{6}$, then the sum of value of $k$ and all possible values of $N$ is
The value of $\left| {\,\begin{array}{*{20}{c}}{41}&{42}&{43}\\{44}&{45}&{46}\\{47}&{48}&{49}\end{array}\,} \right| = $
The number of solutions of the system of equations $2x + y - z = 7,\,\,x - 3y + 2z = 1,\,x + 4y - 3z = 5$ is
If the system of equations $\alpha x+y+z=5, x+2 y+$ $3 z=4, x+3 y+5 z=\beta$ has infinitely many solutions, then the ordered pair $(\alpha, \beta)$ is equal to:
If the system of equations, $x + 2y -3z = 1, (k + 3) z = 3, (2k + 1)x + z = 0$ is inconsistent, then the value of $k$ is :-