1
IIT-JEE 2007
+3
-0.75
Let the vectors $$\overrightarrow {PQ} ,\,\,\overrightarrow {QR} ,\,\,\overrightarrow {RS} ,\,\,\overrightarrow {ST} ,\,\,\overrightarrow {TU} ,$$ and $$\overrightarrow {UP} ,$$ represent the sides of a regular hexagon.

STATEMENT-1: $$\overrightarrow {PQ} \times \left( {\overrightarrow {RS} + \overrightarrow {ST} } \right) \ne \overrightarrow 0 .$$ because
STATEMENT-2: $$\overrightarrow {PQ} \times \overrightarrow {RS} = \overrightarrow 0$$ and $$\overrightarrow {PQ} \times \overrightarrow {ST} \ne \overrightarrow 0 \,\,.$$

A
Statement-1 is True, Statement-2 is True; Statement-2 is a correct explanation for Statement-1.
B
Statement-1 is True, Statement-2 is True; Statement-2 is NOT a correct explanation for Statement-1.
C
Statement-1 is True, Statement-2 is False
D
Statement-1 is False, Statement-2 is True.
2
IIT-JEE 2006
+3
-0.75
A plane which is perpendicular to two planes $$2x - 2y + z = 0$$ and $$x - y + 2z = 4,$$ passes through $$(1, -2, 1).$$ The distance of the plane from the point $$(1, 2, 2)$$ is
A
$$0$$
B
$$1$$
C
$$\sqrt 2$$
D
$$2\sqrt 2$$
3
IIT-JEE 2006
+3
-0.75
Let $$\overrightarrow a = \widehat i + 2\widehat j + \widehat k,\,\overrightarrow b = \widehat i - \widehat j + \widehat k$$ and $$\overrightarrow c = \widehat i + \widehat j - \widehat k.$$ A vector in the plane of $$\overrightarrow a$$ and $$\overrightarrow b$$ whose projection on $$\overrightarrow c$$ is $${1 \over {\sqrt 3 }},$$ is
A
$$4\widehat i - \widehat j + 4\widehat k$$
B
$$3\widehat i + \widehat j - 3\widehat k$$
C
$$2\widehat i + \widehat j - 2\widehat k$$
D
$$4\widehat i + \widehat j - 4\widehat k$$
4
IIT-JEE 2005 Screening
+4
-1
A variable plane at a distance of the one unit from the origin cuts the coordinates axes at $$A,$$ $$B$$ and $$C.$$ If the centroid $$D$$ $$(x, y, z)$$ of triangle $$ABC$$ satisfies the relation $${1 \over {{x^2}}} + {1 \over {{y^2}}} + {1 \over {{z^2}}} = k,$$ then the value $$k$$ is
A
$$3$$
B
$$1$$
C
$${1 \over 3}$$
D
$$9$$
EXAM MAP
Medical
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