The angle between two unit-magnitude coplanar vectors P(0.866,

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The angle between two unit-magnitude coplanar vectors P(0.866, 0.500, 0) and Q(0.259, 0.966, 0) will be

1. 0°
2. 30°
3. 45°
4. 60°

Correct Option: C

P = 0.866î + 0.500ĵ + 0k̂
Q = 0.259î + 0.966ĵ + 0k̂
∴ P.Q = | P | | Q | cosθ
0.866 × 0.259 + 0.5 × 0.966
√0.866² + 0.5² × √0.259² + 0.966² . cosθ
∴ cosθ = 0.707
θ = 45°