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QUESTION

Calculate a unit vector which is parallel to $2{\bf i}-3{\bf
j}+6{\bf k}$.

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ANSWER

Unit vector
$\ds=\pm\frac{2\mathbf{i}-3\mathbf{j}+6\mathbf{k}}{\sqrt{2^2+(-3)^2+6^2}}
=\pm\frac{1}{7}(2\mathbf{i}-3\mathbf{j}+6\mathbf{k})$




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