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

Question

Philoid · Accepted Answer

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

⇒

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