WB JEE 2018 | Vector Algebra Question 12 | Mathematics

WB JEE 2018

MCQ (Single Correct Answer)

-0.5

Let $$\overrightarrow \alpha $$, $${\overrightarrow \beta }$$, $${\overrightarrow \gamma }$$ be the three unit vectors such that $$\overrightarrow \alpha .\overrightarrow \beta = \overrightarrow \alpha .\overrightarrow \gamma = 0$$ and the angle between $$\overrightarrow \beta $$ and $$\overrightarrow \gamma $$ is 30$$^\circ$$. Then $$\overrightarrow \alpha $$ is

2($$\overrightarrow \beta $$ $$ \times $$ $$\overrightarrow \gamma $$)

$$-$$ 2($$\overrightarrow \beta $$ $$ \times $$ $$\overrightarrow \gamma $$)

$$ \pm $$ 2($$\overrightarrow \beta $$ $$ \times $$ $$\overrightarrow \gamma $$)

($$\overrightarrow \beta $$ $$ \times $$ $$\overrightarrow \gamma $$)

WB JEE 2017

MCQ (Single Correct Answer)

-0.5

For any vector x, where $$\widehat i$$, $$\widehat j$$, $$\widehat k$$ have their usual meanings the value of $${(x \times \widehat i)^2} + {(x \times \widehat j)^2} + {(x \times \widehat k)^2}$$ where $$\widehat i$$, $$\widehat j$$, $$\widehat k$$ have their usual meanings, is equal to

$$|x{|^2}$$

2$$|x{|^2}$$

3$$|x{|^2}$$

4$$|x{|^2}$$

WB JEE 2017

MCQ (Single Correct Answer)

-0.5

If the sum of two unit vectors is a unit vector, then the magnitude of their difference is

$$\sqrt 2 $$ units

2 units

$$\sqrt 3 $$ units

$$\sqrt 5 $$ units

WB JEE Subjects