1
IIT-JEE 2001 Screening
+4
-1
Let $$\overrightarrow a = \overrightarrow i - \overrightarrow k ,\overrightarrow b = x\overrightarrow i + \overrightarrow j + \left( {1 - x} \right)\overrightarrow k$$ and
$$\overrightarrow c = y\overrightarrow i - x\overrightarrow j + \left( {1 + x - y} \right)\overrightarrow k .$$ Then $$\left[ {\overrightarrow a \,\overrightarrow b \,\overrightarrow c } \right]$$ depends on
A
only $$x$$
B
only $$y$$
C
Neither $$x$$ Nor $$y$$
D
both $$x$$ and $$y$$
2
IIT-JEE 2001 Screening
+4
-1
If $$\overrightarrow a \,,\,\overrightarrow b$$ and $$\overrightarrow c$$ are unit vectors, then $${\left| {\overrightarrow a - \overrightarrow b } \right|^2} + {\left| {\overrightarrow b - \overrightarrow c } \right|^2} + {\left| {\overrightarrow c - \overrightarrow a } \right|^2}$$ does NOT exceed
A
$$4$$
B
$$9$$
C
$$8$$
D
$$6$$
3
IIT-JEE 2000 Screening
+4
-1
If the vectors $$\overrightarrow a ,\overrightarrow b$$ and $$\overrightarrow c$$ form the sides $$BC,$$ $$CA$$ and $$AB$$ respectively of a triangle $$ABC,$$ then
A
$$\overrightarrow a .\overrightarrow b + \overrightarrow b .\overrightarrow c + \overrightarrow c .\overrightarrow a = 0$$
B
$$\overrightarrow a \times \overrightarrow b = \overrightarrow b \times \overrightarrow c = \overrightarrow c \times \overrightarrow a$$
C
$$\overrightarrow a .\overrightarrow b = \overrightarrow b .\overrightarrow c = \overrightarrow c .\overrightarrow a$$
D
$$\overrightarrow a \times \overrightarrow b + \overrightarrow b \times \overrightarrow c + \overrightarrow c \times \overrightarrow a = \overrightarrow 0$$
4
IIT-JEE 2000 Screening
+4
-1
Let the vectors $$\overrightarrow a ,\overrightarrow b ,\overrightarrow c$$ and $$\overrightarrow d$$ be such that
$$\left( {\overrightarrow a \times \overrightarrow b } \right) \times \left( {\overrightarrow c \times \overrightarrow d } \right) = 0.$$ Let $${P_1}$$ and $${P_2}$$ be planes determined
by the pairs of vectors $$\overrightarrow a .\overrightarrow b$$ and $$\overrightarrow c .\overrightarrow d$$ respectively. Then the angle between $${P_1}$$ and $${P_2}$$ is
A
$$0$$
B
$${\pi \over 4}$$
C
$${\pi \over 3}$$
D
$${\pi \over 2}$$
EXAM MAP
Medical
NEET