1
AIEEE 2004
+4
-1
Let $$\overrightarrow a ,\overrightarrow b$$ and $$\overrightarrow c$$ be three non-zero vectors such that no two of these are collinear. If the vector $$\overrightarrow a + 2\overrightarrow b$$ is collinear with $$\overrightarrow c$$ and $$\overrightarrow b + 3\overrightarrow c$$ is collinear with $$\overrightarrow a$$ ($$\lambda$$ being some non-zero scalar) then $$\overrightarrow a + 2\overrightarrow b + 6\overrightarrow c$$ equals to :
A
$\overrightarrow{0}$
B
$$\lambda \overrightarrow b$$
C
$$\lambda \overrightarrow c$$
D
$$\lambda \overrightarrow a$$
2
AIEEE 2004
+4
-1
Let $$\overrightarrow a ,\overrightarrow b$$ and $$\overrightarrow c$$ be non-zero vectors such that $$\left( {\overrightarrow a \times \overrightarrow b } \right) \times \overrightarrow c = {1 \over 3}\left| {\overrightarrow b } \right|\left| {\overrightarrow c } \right|\overrightarrow a \,\,.$$ If $$\theta$$ is the acute angle between the vectors $${\overrightarrow b }$$ and $${\overrightarrow c },$$ then $$sin\theta$$ equals :
A
$${{2\sqrt 2 } \over 3}$$
B
$${{\sqrt 2 } \over 3}$$
C
$${2 \over 3}$$
D
$${1 \over 3}$$
3
AIEEE 2003
+4
-1
If $$\overrightarrow a \times \overrightarrow b = \overrightarrow b \times \overrightarrow c = \overrightarrow c \times \overrightarrow a$$ then $$\overrightarrow a + \overrightarrow b + \overrightarrow c =$$
A
$$abc$$
B
$$-1$$
C
$$0$$
D
$$2$$
4
AIEEE 2003
+4
-1
Let $$\overrightarrow u = \widehat i + \widehat j,\,\overrightarrow v = \widehat i - \widehat j$$ and $$\overrightarrow w = \widehat i + 2\widehat j + 3\widehat k\,\,.$$ If $$\widehat n$$ is a unit vector such that $$\overrightarrow u .\widehat n = 0$$ and $$\overrightarrow v .\widehat n = 0\,\,,$$ then $$\left| {\overrightarrow w .\widehat n} \right|$$ is equal to :
A
$$3$$
B
$$0$$
C
$$1$$
D
$$2$$
EXAM MAP
Medical
NEET