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If a line makes angles π2,34π and π4 with x, y, z axis, respectively, then its direction cosines are ______. - Mathematics

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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 `+- (0, - 1/sqrt(2) 1/sqrt(2))`.

Explanation:

The direction cosines are `cos  pi/2, cos  3/4 pi, cos  pi/4`

i.e., `+- (0, - 1/sqrt(2) 1/sqrt(2))`.

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Chapter 11: Three Dimensional Geometry - Solved Examples [Page 233]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 11 Three Dimensional Geometry
Solved Examples | Q 20 | Page 233

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