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The direction cosines of 2i − 3j + 6k are
A1/3, −1/3, 1/3
B2/9, −3/9, 6/9
C2/5, −3/5, 6/5
D2/7, −3/7, 6/7
Answer & Solution
Correct answer: D. 2/7, −3/7, 6/7
The magnitude is 7, and dividing each component by 7 gives the direction cosines.
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