Question

The angle θ between the vectors $\rm \vec{a} = 5\hat{i} - \hat{j} + \hat{k}$ and $\rm \vec{b} = \hat{i} + \hat{j} - \hat{k}$ equals to

• A. cos-1θ(13)
• B. cos-1θ(23)
• C. cos-1θ(47)
• D. None of these

Answer 1

Answer: (A)

cos-1θ(13)

Answer 2

The correct answer is (A): cos-1θ(13)