Two vertices of $\triangle ABC$: $(2,4,6)$, $(0,-2,-5)$; centroid $(2,1,-1)$. Third vertex $C=(4,1,2)$. Image of $C$ in $x+2y+4z=11$ is $(\alpha,\beta,\gamma)$. $\alpha\beta+\beta\gamma+\gamma\alpha$ is equal to
Let $A(x,y,z)$ be a point in $xy$-plane, which is equidistant from three points $P(0,3,2)$, $Q(2,0,3)$ and $R(0,0,1)$. Let $B=(1,4,-1)$ and $C=(2,0,-2)$. Then among the statements
(S1): $\triangle ABC$ is an isosceles right angled triangle, and
(S2): the area of $\triangle ABC$ is $\dfrac{9\sqrt{2}}{2}$
Let L : y-1 y z+4 1 x-1 3 = -1 = z+1 0 and L : 2 x-2 2 = 0 = \alpha ,\alpha \in R , be two lines, which intersect at the point B. If P is the foot of perpendicular from the point A(1, 1, -1) on L , then the value of 26\alpha( PB) is _________ 2 2
Let a unit vector $\overrightarrow{OP}$ make angles $\alpha, \beta, \gamma$ with the positive directions of the co-ordinate axes OX, OY, OZ respectively, where $\beta \in \left(0, \frac{\pi}{2}\right)$. $\overrightarrow{OP}$ is perpendicular to the plane through points $(1,2,3)$, $(2,3,4)$ and $(1,5,7)$. Then which one of the following is true?
Find the length of the projection of vector $\vec{AB}$ onto the normal vector to a plane, where $A = (1, 2, -1)$, $B = (3, 5, 5)$, and the normal vector is $3\vec{i} - 4\vec{j} + 12\vec{k}$.
Image of $P(1,2,6)$ in plane through $A(1,2,0)$, $B(1,4,1)$, $C(0,5,1)$ is $Q(\alpha,\beta,\gamma)$. Then $\alpha^2+\beta^2+\gamma^2$ is equal to
Plane through $(0,-1,2)$ and $(-1,2,1)$, parallel to line through $(5,1,-7)$ and $(1,-1,-1)$. Which point lies on it?
A vector $\vec{v}$ in the first octant is inclined to the x-axis at $60°$, to the y-axis at $45°$ and to the z-axis at an acute angle. If a plane passing through the points $(\sqrt{2}, -1, 1)$ and $(a, b, c)$, is normal to $\vec{v}$, then
Normal vector to the plane $P = 0$ is $\begin{vmatrix} \vec{i} & \vec{j} & \vec{k} \\ 2 & -1 & 2 \\ 3 & 6 & -2 \end{vmatrix} = \vec{i}(-10) - \vec{j}(-10) + \vec{k}(15) = -10\vec{i} + 10\vec{j} + 15\vec{k}$. Equation of the plane through $(1, 1, 1)$ is $-2(x - 1) + 2(y - 1) + 3(z - 1) = 0$. So, the distance from the point $(1, 2, 3)$ is $\left|\frac{-1 + 3 - 3}{\sqrt{17}}\right| = \frac{1}{\sqrt{17}}$ units.
If the foot of the perpendicular drawn from $(1, 9, 7)$ to the line passing through the point $(3, 2, 1)$ and parallel to the planes $x + 2y + z = 0$ and $3y - z = 3$ is $(\alpha, \beta, \gamma)$, then $\alpha + \beta + \gamma$ is equal to
The point of intersection C of the plane $8x + y + 2z = 0$ and the line joining the points $A(-3, -6, 1)$ and $B(2, 4, -3)$ divides the line segment AB internally in the ratio $k:1$. If $a, b, c$ ($|a|, |b|, |c|$ are coprime) are the direction ratios of the perpendicular from the point C on the line $\frac{1-x}{1} = \frac{y+4}{2} = \frac{z+2}{3}$, then $|a+b+c|$ is equal to _____.
$P_1:\ 3x-y-7z=11$; $P_2$ through $(2,-1,0),(2,0,-1),(5,1,1)$. Foot of perpendicular from $(7,4,-1)$ on $P_1\cap P_2$ is $(\alpha,\beta,\gamma)$. Then $\alpha+\beta+\gamma$ is equal to