Maths-
General
Easy
Question
Let the unit vectors 
and 
be perpendicular and the unit vector 
be inclined at an angle θ to both and 
If
then
- None of these
Hint:
We are given three unit vectors. Two of the vectors are perpendicular and the two vectors make same angle with the third be vector. We are given the third vector. We have to find the values of the variables of the third vector.
The correct answer is:
The given unit vectors are 
So, 
We are given that 
The vectors 
makes angle θ with the vector 
.
The vector is given as
We have to find the values of 
.
Let's take the dot product of the vectors.
...( Both are perpendicular)
Let's substitute value of
We will substitute the value of
Now, we will do following multiplication 
We have all the three values now.
We should know how to take dot product of two vectors.
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