Unit 13.1 Worked Example 4

Unit 13.1 Worked Example 4

TGM Original Questions
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Given two vectors \(\mathbf{a}=2\mathbf{i}+\mathbf{j}-2\mathbf{k}\) and \(\mathbf{b}=\mathbf{j}+3\mathbf{k}\), find:

  1. a unit vector perpendicular to both \(\mathbf{a}\) and \(\mathbf{b}\).
  2. the exact value of \(\sin \theta \), where \(\theta \) is the angle between \(\mathbf{a}\) and \(\mathbf{b}\).

Video Solution:

Default solution

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Answer:(i) \(\displaystyle\frac{1}{\sqrt{90}} \begin{pmatrix} 7 \\\\ -4 \\\\ 5 \end{pmatrix}\); (ii) \(\sin\theta = \sqrt{\displaystyle\frac{5}{13}}\)

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