Q32 of 181 Page 1073

If and are unit vectors such that is a unit vector, what is the angle between and ?

It is given that are unit vectors ,as well as is also a unit vector


⇒|| = || = || = 1


Since the modulus of a unit vector is unity.


Now,


||2 = ||2 + ||2 + 2||||cosθ


⇒12 = 12 + 12 + 2×1×1× cosθ


⇒ cosθ = (1 - 1 - 1)/2


⇒


⇒


Ans:


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