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Question
The direction cosines of the vector `(2hati + 2hatj - hatk)` are ______.
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Solution
The direction cosines of the vector `(2hati + 2hatj - hatk)` are `2/3, 2/3, (-1)/3`.
Explanation:
Direction cosines of `(2hati + 2hatj - hatk)` are
`2/sqrt(4 + 4 + 1)`, `2/sqrt(4 + 4 + 1)`, `(-1)/sqrt(4 + 4 + 1)`
i.e., `2/3, 2/3, (-1)/3`
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