Angle between vectors (hat{i} + hat{j}) and (hat{i} - hat{k}) is ........ ^o

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3-1.Vectors

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Angle between the vectors $(\hat i + \hat j)$ and $(\hat i - \hat k)$ is ........ $^o$

A$90$

B$0$

C$180$

D$60$

Solution

(d) $\cos \theta = \frac{{\vec A.\vec B}}{{|\vec A||\vec B|}} = \frac{1}{{\sqrt 2 \sqrt 2 }} = \frac{1}{2}$ $\theta = 60^\circ $

Standard 11

Physics

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