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Question
If a line makes angles `pi/2, 3/4 pi` and `pi/4` with x, y, z axis, respectively, then its direction cosines are ______.
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Solution
If a line makes angles `pi/2, 3/4 pi` and `pi/4` with x, y, z axis, respectively, then its direction cosines are `+- (- 1/sqrt(2) 1/sqrt(2))`.
Explanation:
The direction cosines are `cos pi/2, cos 3/4 pi, cos pi/4`
i.e., `+- (- 1/sqrt(2) 1/sqrt(2))`.
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