Question

Let  be vectors of equal magnitude such that the angle between  Then, the minimum value of the cos α + cos β + cos γ is

Solution

Correct option is

– 3/2 

 

  

We have,  

       

       

       

Now,

       

   

  

Hence, the minimum value of 

SIMILAR QUESTIONS

Q1

If  are unit vectors such that 

Q2

If  are unit vectors such that  and  then 

Q3

If  are unit vectors inclined to x-axis at angles 30o and 120o, then  equals

Q4

If  are three vectors such that 

Q5

Let  be three vectors such that  and  If 

Q6

If two out of the three vectors  are unit vectors such that  then the length of the third vector is   

Q7

Let  be three unit vectors such that  and  If  makes angles δ, β with  respectively, then  is equal to

Q8

Let  be three unit vectors such that angle between  is  If  then cos α + cos β + cos γ = 

Q9

Let  be three unit vectors such that angle between  is  If  then cos α + cos β + cos γ = 

Q10

Let  be three vectors of equal magnitude such that the angle between each pair is  If