If a and b are unit vectors and a - b is also a unit vector, then… - Vidyadip

MCQ

If $ a$ and $ b$ are unit vectors and $a - b$ is also a unit vector, then the angle between $ a $ and $ b$ is

A
$\frac{\pi }{4}$
✓
$\frac{\pi }{3}$
C
$\frac{\pi }{2}$
D
$\frac{{2\pi }}{3}$

✓

Answer

Correct option: B.

$\frac{\pi }{3}$

b
(b) ${(a - b)^2} = 1 = 2 - 2\cos \Rightarrow \,\theta = 60^\circ .$

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